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never steal from a king

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Inching his way down a long trench, Kirishima swam into the unknown, an underwater flare burning brightly in his hand. He was following a path of gemstones and crystals embedded in the black rocks, squeezing through narrow spaces and underneath tight bends. It was uncomfortable and dangerous, the rocks scraping his oxygen tanks, but he knew the path was good. He was getting close to the legendary sea monster, Bakugou Kastuki's, lair.  

After swimming under another tight bend, almost poking a hole through his oxygen tank, Kirishima saw a glimmering blue light and discarded his flare. The light came from large crystals jutting out of the sand at the bottom of a wide entrance, the opening pitch black. Kirishima held his emotions at bay as he swam to the opening. He didn't let his excitement get to him; he was disciplined.  

Closer he swam, staring at the entrance and squinting, seeing nothing. Kirishima went inside, swallowed up by the impenetrable darkness. He figured he swam a total of twenty yards when he saw more light in the distance, burning the same shade of blue back at the entrance. Coming closer to the light, Kirishima saw more blue crystals guarding another opening much smaller in comparison to the first one.  

He investigated the opening, finding it sizeable enough for him to fit his head and shoulders through. His oxygen tanks were going to be a problem, however. Kirishima pushed himself into the entrance, going slow as to not rupture his air supply, and emerged inside an underwater den. A large rock pillar shot up from the ground, supporting a wide circular roof. Coral protruded out of the sides in varying lengths, some nearly touching the roof. Different colored crystals extended from the ceiling, shining glittering light over heaps of gold, precious stones, and trinkets.  

The amount was staggering. Kirishima swam forward, his eyes bulging behind his large goggles. It was tempting to take all of the treasure belonging to the sea monster, but he was only here for two doubloons.  

Kirishima swept his gaze across the bountiful stacks of riches. He'd be lucky if he could find one doubloon, let alone two. Like searching for a needle in a haystack, he mused, his brows furrowing into a slight frown. The search was going to take all day.  

As he neared the piles of treasure, sweeping his eyes carefully over the sparkling riches, he noticed another light in his periphery. It was different from the light glowing off the crystals. Lighter and softer, with a touch of warmth that he could feel through the thick neoprene making up his diving suit. Turning his head behind him, Kirishima followed the light to a hole in the ceiling, hidden behind pink staghorn coral. Curiosity piqued, he swam towards it, pushing his head through the hole and peering above the edge.  

The first thing he noticed was that he could breathe. There was no water on the other side, just damp air. Taking off his snorkeling gear, Kirishima gaped into the underwater cave. Blue, green, and yellow crystals were sticking out of the rock walls, lighting the place in a variety of colors. Staghorn and black coral grew in between the crystals, most covering them up completely. There was no water, and yet the organisms were able to thrive. How? The ground was made of soft sand that Kirishima's hand sunk through, crunching ever so quietly underneath his fingers.  

The second thing he noticed was the treasure. Piles of it lay everywhere, the bases surrounded by frilly pink and blue sea pens. How was that possible if there was no water for the coral to thrive in? Kirishima ran his eyes over the piles, gawking at the jaw-dropping sight. It took two full sweeps to take it all in, and then his gaze fell over the creature. It was huge.  

No, Kirishima squinted, he was huge. His skin was pale, mottled with scars and gashes from previous battles. Muscle rippled down arms and across broad shoulders. Iridescent black scales ran down his biceps and fingers, the tips ending in 3" black claws. A long, muscular tail curled around him, spikes going down his spine and ending at opaque fins. The sea monster was asleep.  

Kirishima was staring at Bakugou, not expecting to find him at all and in a vulnerable position. He sucked in a breath as the creature stirred, rolling his tail over his glittering gold nest. Inspecting the shiny gold, Kirishima cursed his luck. He just had to be sleeping on top of a pile of doubloons and gems.  

He carefully pulled himself out of the water, unhooking his oxygen tanks and placing them on the sand. A large bubble inflated and deflated, covering the merman's face as he snored away. At least he was sleep, Kirishima thought. He would have had to wait otherwise if he wasn't.  

He crept stealthily across the soft sand, listening for any changes in Bakugou's snoring. He approached the glittering bed, raking his eyes over the abundance of the ancient coins and gems. Carefully, he plucked a coin. And then another. His eyes drifted up, staring at the slumbering merman's face.  

He was beautiful. Black scales dotted his cheeks, adding shine to his snow-white complexion. Kirishima could make out traces of scars that added another layer of beauty to his appearance. One ran from his hairline to just below his cheek, cutting over his eye. Black ear fins stuck out of blond hair, the left one ripped at the tips. Kirishima wondered, what creature could have fought the merman? Gazing at his full lashes and thick eyebrows, he turned around and made his way back to the opening, sliding the two coins inside his suit.  


Kirishima was strapping on his gear when he heard the sound explode behind him, the noise a cannon going off in a quiet room. The atmosphere suddenly shifted and the hairs along his neck and shoulder rose. Slowly, Kirishima turned his head.  

Bakugou was awake and rising off his bed. His eyes were wide open and glaring at Kirishima, irises a fiery shade of red framed by black sclera. Thin black pupils dilated as they locked onto the diver and his lips pulled back, exposing two rows of curved teeth. A low snarl emitted deep from the bowels of his throat, filling the cave with its harsh sound.  

Kirishima nearly pissed himself hearing the guttural noise. Bakugou placed his hand forward, dragging his massive body off of his nest. Coins and gems skittered underneath the weight as they were disturbed, sprawling across the white sand. Black frills rose behind his shoulder blades, sprouting like ebony wings and rattling like the tip of a rattlesnake's tail. The sound was haunting, turning Kirishima's blood to ice. The two coins he stole pressed into his chest, hard and heavy and cold as lead.  

He emitted another low growl and Kirishima pivoted on his feet, dashing for the hole in the ground. A deafening screech erupted behind him, popping his eardrums. Diving back into the water, Kirishima kicked his legs hard, dashing to the exit. Water sloshed around him and he turned around to see the merman diving after him, snarling wickedly.  

In the water he looked bigger, almost reaching the size of a small whale. Kirishima swam as fast as he could for the exit, but it wasn't fast enough. Bakugou's speed was immeasurable; he caught up to him quick, striking him dead in the back with his tail.  

It felt like a car hit him. Kirishima was sent flying into a wall, cracking his head against the rocky surface and rupturing both of his oxygen tanks. He saw the merman darting towards him in his fading vision, his teeth bared and glinting. With Herculean effort, Kirishima struggled to swim out of the way, but another bone-jarring hit had him careening onto the seafloor.  

He blacked out instantly.  




Kirishima's world was dark. He couldn't see anything, only feel and hear, and he heard shuffling all around him. Sand shifted underneath his body, getting trapped underneath spots in his diver suit.  

Several times he tried blinking awake, only finding himself unable to do so. The shuffling around him stopped and Kirishima felt heat swamp his body, burning him from his toes to his forehead. He struggled to open his eyes as the pressuring heat increased, letting out a soft groan. 

All of a sudden, a heavy weight pressed dead center on his chest, snapping his eyes open to a bright world. Kirishima gasped once the weight was off of him, rapidly blinking to take in his surroundings. "The thief finally decides to wake up."  

The voice was deep and guttural, sounding like it came from all over. Once his vision was focused, Kirishima glanced around the cavern, sweeping his eyes over the piles of treasure searching for where the voice was coming from. "You almost thought you could get away with my treasure too. I ought to gut you for that, shitty-human."  

His attention was brought down to the heavy weight returning to his chest, pushing on his rib cage. Kirishima looked at the merman's face looming over him, trapped underneath his carmine gaze. He let out a soft growl and sunk the tips of his claws through the thick material of his diving suit, pricking skin underneath. The two doubloons he stole painfully dug into his skin. Kirishima groaned softly.  

"Tell me your name, what your purpose is here, and why I shouldn't rip your heart out of your chest."  

The weight steadily increased. Kirishima doubted he had the energy to speak. He tried moving around, but weight from his own agony and the merman's hand kept him pinned in one spot. He swallowed a heavy lump down his throat, testing his vocal cords. "Kirishima," he breathed, quietly.  

Weight was lessened off his chest. "I can't hear you. Speak up, now."  

"I'm Kirishima... Eijirou...!" He gasped his name, breathing heavily as more weight was added to his chest, "And I'm a lost traveler searching for my boat." By the end of it, he was panting like he had run a marathon. Bakugou let up on the pressure to his chest but never took his hand off of it. He glared at the red-faced diver, pulling his lips over his teeth and furrowing his brows in a deep scowl. Kirishima gulped.  

"Your boat's not anywhere in my den, human."  

"I was searching for it—" 

The pressure came back tenfold. "I know exactly what you were doing hereYou're here to steal my treasure and keep it for yourself. You're no traveler, you're a thief. And you thought you could take from me."  

The merman's hand was crushing his rib cage into his body. Kirishima felt several bones creak, threatening to snap under his weight. The tips of his claws push deeper into his suit, welts of blood glistening red around the black keratin. Kirishima squirms under the pain, mouth going slack with keening whines pushing over his lips.  

"I'm not a thief," he explained to the merman, but Bakugou didn't hear him. Either that, or he ignored him. "Please, don't kill me."  

Bakugou shook his head. "It would be so easy, too. All I'd have to do is this," He pushed harder down on his chest and Kirishima screamed, "and you'd be dead. I can rip out your heart," He dragged his claws over the beating organ, filling his brain with gruesome images of him bleeding out across the sand, "and your life would be over. But that wouldn't be fair. You tried taking something precious from me, shitty-haired thief."  

Kirishima wrenched his jaws open but promptly snapped them as Bakugou tore open the front of his suit. The tough neoprene ripped away like wet paper. He had been a fool thinking it would protect him from the claws of the sea monster.  

The golden doubloons fell out and rolled onto the sand next to his arms. Heat swamped over Kirishima, singing the thin skin on top of his ears. Bakugou took his hand off his chest to grab them and rolled the two coins between his fingers, staring at them with a hardened gaze. "Because of that, I have something much better planned for you, you thieving monkey son of a bitch."  

"A-Are you going to eat me?" Kirishima hated how weak and frail he sounded. Bakugou tossed the coins behind him where they landed on his nest in quiet plinks. "I don't eat humans," he growled, looming over him, "too skinny for me. Since you thought it was okay for you to swim your two-legged ass in my den and take something precious from me, I'll just take something precious from you. It only seems fair, right?"  

He sneered, "A just punishment you hardly deserve, thief, but one I'm willing to give you in exchange for your life."  

Kirishima wondered what he meant by all of this. He wasn't making any sense; just punishment? Taking something precious from him? His life was precious at the moment, incredibly so. What was he going to take? Bakugou's smirk grew in full, covering the entire expanse of his face, exposing both rows of his sharp teeth.  

He understood completely at the moment and shuddered violently. "W-wait," he stuttered as Bakugou fell on top of him, "hold on. C-can't we work something out?" The beast slotted his hips in between Kirishima's thighs, forcing them apart to take in his wide stance. "There's nothing to work out, shitty-hair," he hummed over his lips, their faces centimeters apart. Kirishima smelled the ocean on his breath, as well as another scent laced underneath it.  

Spice, infused with a leathery aroma. Kirishima felt his mind turn sluggish as the sea monster's scent enveloped him. Bakugou lowered his mouth close to his neck, brushing his lips over his skin, smiling at how it shivered. Parting them, his tongue slid along his skin, licking the sweat, sand, and dried seawater covering it and humming contently.  

"I don't eat humans," he said, "but I do enjoy the taste. Very much so."  

Kirishima trembled as his tongue wrapped around his neck. It's long, able to go around his neck once and tease the inside of his right ear. He unwraps his tongue and replaces it with teeth, lightly nipping the wet patches of skin until light bruises bloomed. Kirishima let out a strangled moan as the merman's teeth scraped a sensitive patch of skin directly under his jaw, sending burning arousal in between his legs.  

Bakugou pulled and tugged the skin until a large hickey blossomed and pulled back to admire his handiwork, smirking proudly. His skin was flushed red and sporting several different sized bruises like a necklace across his neck. Kirishima's stomach churned as his predicament became eerily clearer. His blood runs cold inside of his veins and sweat beaded across his forehead.  

The merman leaned close to his face, bringing his ugly smirk closer. More of his scent wraps around Kirishima's head, clogging his nostrils in its intoxicating aroma. He felt as if he was drunk, muscles turning into jelly under his skin as the sea monster covered him in his scent. Bakugou pushed his face closer until his lips were centimeters apart from Kirishima's parted mouth, and he kissed him. Hard.  

He didn't expect the beast to kiss him softly, but it still took him by surprise. Bakugou sunk his teeth into his bottom lip and pulled it back before soothing the tip of his tongue over it, repeating the cycle several times. He rolls his hips above Kirishima, working his throbbing arousal until it was strained, trapped behind the thick neoprene.  

Kirishima's mouth fell open to moan, but the sound was swallowed up as the merman's long tongue pushed inside, turning the hard kiss sloppy. He teased the tip of his tongue along his gums and pallet and reached further, licking the back of his throat and down. Letting out a slew of gargles, Kirishima fought to keep up with Bakugou, kissing him back just as hard, but he can't. The merman dominates the inside of his mouth, taking control of the kiss. He sets the pace, and all Kirishima can do is try to keep up.  

Bakugou grinds harder and Kirishima swears he can feel it, his cock hardening like a rock under his suit. Sliding his tongue over his tonsils, Bakugou pulled out of his mouth, licking up the drool dribbling from the corners. He smirks, and Kirishima knows he can feel it. Gives him a teasing flick of the hips as he rises, pulling his chest off of his.  

Kirishima inhales, he can breathe again. He takes in as much air as he could, glancing down Bakugou's body as he did so, marveling at the defined muscles of his abs and V-line, his skin covered in a thin lining of black scales. "Like what you see?" The merman rolled his shoulders back, flexing his hard muscles and showing off for him. He smirked at the way Kirishima's eyes glinted, at how his breathing turned sharp and quick.  

He looked further down his body, going over the shiny scales covering his tail. From there, he sees it—rather, them. From the merman's lower body, a slit opened, and two pink points were revealed, pushing out in a drawn-out squelch. Two cocks extruded like tongues, long and thick, the sides corrugated. Fleshy pink in color, they flared at the base, disgorging two knots thicker than both of Kirishima's wrists. Both of his cocks were wet.  

Kirishima looked back up at Bakugou's face. One could have barely fit inside him; two would have been impossible. Noticing the uncertainty in his eyes had Bakugou quietly snickering under his breath. Trepidation settled in the middle of Kirishima's gut, weighing the organ down. He wouldn't... would he?  

"What's with the face, shitty thief? You looked like you were into it a minute ago. What happened?"  

Kirishima switched his gaze back to his cocks, swallowing at the sight of them. The two knots started to twitch. They were still growing. Kirishima felt both of the merman's hands grab his hips, and in one swift motion he turned him over so he was on his hands and knees, his ass pointed to him. Claws raked down his back, pressing just hard enough to cut his diving suit, yanking the black and navy-blue material out of the way.  

Kirishima felt his claws go over his rump, following the curves down to the middle of his thighs. Bakugou pulled the torn strips off, making a mess over the sand. His fingers kneaded his ass cheeks together, pushing and spreading the soft muscle apart and exposing his tight entrance. Kirishima gulped. He was about to be fucked raw by the huge sea monster. 

Even worse was that this was his first time. He was going to lose his virginity to a mythical creature of the deep.  

Bakugou laughed like he had heard the thoughts rolling inside of his mind. His breath splashed over his cheeks, warming the skin, and Kirishima jumped. He didn't realize how close the merman was to him. It only made the realization even more sickening.  

"I'm going to have fun with you," he heard him breathe, felt him whisper over his ass he leaned closer to it. His lips touched, and then the sharp points of his teeth as he bit down.  

Kirishima grunted, it felt nice. Strange, but nice. Bakugou nipped more patches of his skin, leaving small bruises in his wake. As he neared the center of his ass, Kirishima felt the warm press of his tongue run over his skin before sliding in between his cheeks.  

That felt incredibly nice. A curious moan slips out, light and quiet. Bakugou does it again, starting from the bottom and going up, and Kirishima moans in full. Saliva drips down, running off his balls and onto the ground. His skin loosens up where the merman's spit touches, and it feels cool over his hot, sensitive skin. 

The tip of the merman's tongue comes in contact with his tight entrance, teasing around the outer ring. He pushes in, slowly, stretching his ass apart. Kirishima groans at the tearing of virgin skin as it was forced to stretch beyond its limit. He covered his face with both of his arms, hiding his flushed cheeks as the merman pushed his tongue deeper. It never seemed to end. Was he attempting to reach his stomach?  

That's what it felt like, minutes later after he stopped. Kirishima felt Bakugou flicking the tip of his tongue inside of his guts, pushing them into his stomach. He had never felt something like this before. It was... odd, but nice. And so damn good.  

The slow thrusts quickened into rapid assaults, leaving Kirishima panting hard into his arm. Claws dug into his skin, drawing welts of blood dripping down his ass, but the pain is nothing compared to the heavy arousal he feels. His cock aches from the stimulation, leaking profusely in between his legs.  

Bakugou pulls his tongue out before Kirishima can cum, and a distressed moan spews over his lips. "Were you enjoying it that much, shitty-hair?" His husky voice pulls Kirishima's face over his shoulders to look at him and he freezes, his eyes widening.  

The merman's red gaze was laced over in a film of lust, turning his eyes hazy. His smile dripped with seduction, whispering soft words over his wet ass. He bit the juncture between his ass cheek and thigh, Kirishima hissing at the soft pain. Licking a stripe over the new mark, Bakugou pulls himself over him, resting his chest on his back. Forcing his chest to the ground while his hips rose, cheeks brushing over the merman's girthy cocks.  

Kirishima shuddered as he felt them pulse hotly on top of his skin. Bakugou ruts his wet lengths over him, stimulating the diver. Kirishima shudders again as his opening dilated. His body was ready for the merman, yearning for him, but his mind was still hesitant. Bakugou kept rolling his hips over his ass. He leaned forward, his mouth close to his ear, and tugged on the lobe with his teeth.  

His hole winked, begging to be filled already. Kirishima wondered why the merman wasn't getting on with it until he felt liquid sluice down his ass, slathering his balls in its warmth. It made him shiver, despite the warmth, and felt like lube. Was Bakugou prepping him?  

Kirishima's stomach flipped. The merman was actually taking his time stretching him open. He figured he would go in and get it over with already and felt wrong for thinking such thing. Yet at the same time, his insides ran cold. Bakugou taking his time meant Kirishima wouldn't leave until he was done. He was stuck here for however long the merman kept him until he was through with his body.  

Bakugou's deep chuckling pulled him out of his thoughts. "You're in luck," he rasped, hot and heavy in his ear, "I'm in heat. Had you decided to pull this stunt when I wasn't, and you might've been rotting in my guts. Though who knows, I might actually eat you after all. You taste so goddamn delicious."  

His tongue lathed up his neck, glancing over patches of bruised and sensitive skin. Kirishima bit his lip to keep his moan from escaping, but it left anyway, tense through his tight lips. Bakugou lowers his hips, and his cocks slide in between Kirishima's legs. Trapped between them was his own length, minuscule compared to them, getting scissored between the ribbed flesh. It was maddening how good it felt and Kirishima spread his legs more, moaning hard and loud.  

The merman's slick squelched between his thighs, sticking to his skin and stretching into thin ropey strands every time he retracted his hips. The wet sensation, coupled with his intoxicating scent, left Kirishima feeling as if he was going through a heat of his own. His skin was flushed all over, and his breathing was labored. Sweat dripped down his face, arms, and back. His stomach clutched, heat coiling into a tight spring in the center that drew tighter and tighter with each roll of the merman's hips.  

"Eijirou," Bakugou whispers his name on a husky breath, and Kirishima cums hard, shouting in ecstasy. An ache spreads through his nuts nestled in between the merman's long cocks, squeezed as they rolled over them. Semen dripped from his tip, forming a white puddle between his legs. Even after coming, Kirishima was still hard. His erection slapped against his stomach as Bakugou pulled his hips back and slid his two lengths up his ass, teasing his hole again. "P-please," Kirishima stammered under a low voice. Bakugou kept grinding his cocks on top of him as he hummed, "Please, what?" " 

He couldn't believe he was doing this. His ears burned at the tips as the words slipped over his lips, hot and full of need.  

"Fuck me, Katsuki ."  

The merman stops rolling his hips. Kirishima looks over his shoulder, a question ready at his lips, but it flies out of his mouth at the same time his soul does. Bakugou gives no warning as he pushes inside, both of his cocks entering him at once. He only makes it halfway, but it went in so fast, tearing and slicing through his tight skin. Kirishima came with a loud scream, his voice bouncing back and forth on the rock walls. Semen sprayed everywhere, coating his exposed skin and the soft sand.  

Bakugou pulled his hips back and pushed deeper, making Kirishima sob. His nails dug into the sand to steady him as his body was thrown into a tumult of stimulations. Bakugou retracted and went deeper, grounding him into the sand. Kirishima gasped, his lungs were getting pushed into his throat. Back out, and then back in, almost down to the knots.  

"You're so goddamn tight," Bakugou growled, cursing under his breath. Back out he went, and he snapped his hips forward, sliding even deeper. His knots pushed through with a wet squelch, and he was fully sheathed inside of Kirishima. He trembled from feeling so full. It should have hurt him, but the only thing he felt was an intense pleasure that made him delirious. How was that possible?  

Kirishima's mind was too drunk to figure it out. Bakugou started moving, setting a brutal pace that left the redhead breathless. Both of his tips pushed a double hump into his stomach—he could feel them distend his skin and grabbed them weakly. The bulges disappeared and came back, more defined than before. Kirishima felt the ribbed flesh pushing through his skin and groaned weakly.  

Bakugou's claws found purchase on his hips and he sunk into them as he slammed their hips flushed. Kirishima whimpered under the heavy assault. Tears form in the corner of his eyes, he's so overwhelmed. Bakugou fucks him mercilessly, beating his prostate every other thrust. "You know," he grunts, lips peeling back into a smile, "I'm starting to think you're enjoying your punishment, Eijirou."  

A mix between a moan and yelp crosses over Kirishima's lips. Bakugou leans over him, placing his hands on either side of his body. His lips closing in on his ear once more, he breathes, "You're sucking me in so nicely, it's hard not to think that. Do you like getting fucked by me, thief?"  

Kirishima mewls in answer, too wired to formulate any words. Bakugou slams both of his cocks into his prostate again and he spills, cum spurting out of a red flared tip. "God," he weakly sobs, that was his fourth time. His balls remained tight, preparing for another load. He didn't know if he could do it.  

Bakugou licked his ear down to his neck with his long tongue, swallowing the sweat and sand sticking to it. He lowers his hips so that his thrusts were angling up, striking Kirishima's prostate dead on. He fell forward, tongue lolling out and drool running down his chin. "You're a mess," Bakugou breathed, nearing his face and sneering. He flips him, throwing the diver under a hazy stare.  

Kirishima stares at the merman's maniac expression, barely able to focus on it as he was fucked raw. His thighs quiver as they clutch around his thrusting hips, unable to hold on. His arms and hair are splayed above him, sand sticking to them from sweat. Bakugou traces a claw down his cheek, unconsciously leaning forward.  

Without thinking, Kirishima surges up, closing the small gap.  

It's harder than their first kiss. Bakugou kisses him like a punishment, shoving his lengthy tongue deep down his throat. Kirishima suckles on the wet velvety muscle, emitting a guttural groan out of the merman.  

Bakugou pulls back and flips him again, putting him back in his previous position. Supporting himself with his arm, Kirishima covered his mouth with his other hand, but it did nothing to stop the tortured moans from belting out of his throat one after another. He felt Bakugou's large hand touch his fingers and grabbed it unconsciously, twining his fingers around the scaly digits.  

The merman nipped his shoulder and nuzzled the side of his face, tightening his grip around Kirishima's hand. "Eijirou," he groaned, biting his cheek, "look at me." Kirishima swallowed excess spit and turned his head, dropping his hand onto the sand.  

He could hardly see Bakugou's face except for his eyes, but that was enough for him. Bakugou's expression was scrunched in arousal, his brows furrowing into a sharp V on his forehead. He growled onto Kirishima's cheek, the sound vibrating over his chest, pushing a weak climax through Kirishima's aching cock. ""  

Heat floods him, pouring straight into his stomach. The amount nearly makes Kirishima black out, his vision darkening in the corners. Bakugou thrusts into him once, spewing his thick cum into his body, and then pulled out, leaving one tip in as the other cock pressed in between his thighs, the knot swelling over his skin. He shoved himself back in deep and let out a strange, high-pitched grunt like he was giving birth.  

Warm fluid rushed into his guts, and then something else. Small and oval-shaped, plopping inside of Kirishima and flooding down the channel into his stomach. One, two, three, four—Kirishima lost count after ten of them. The phenomenon tugged a memory out of his brain, about Bakugou saying he was in heat. He hadn't thought about it at the time, but now it became all too clear:  

The merman was breeding him.  

Kirishima came his hardest yet after realizing that. Bakugou grunted as he clutched around, gripping his hips in a white-knuckled grasp. Kirishima screeched through his powerful climax before falling limp, his cock dribbling semen in a steady line onto a widening puddle.  

The last egg slipped inside him, scraping his prostate. Bakugou sighed heavily in his ear, licking his lobe as he pulled out of him in a deep, drawn-out squelch. Both of his cocks softened before slithering back into their slits, never to be seen again.  

Kirishima was exhausted, thoroughly fucked out. Words wouldn't even form on his tongue; it was like he had lost the ability to speak. Bakugou flipped him over, too boneless to move himself, smiling at his worn expression. Kirishima's vision was beginning to fade out as exhaustion took over him. "Don't fall asleep just yet."  

Bakugou's voice was pure silk in his ears, wrapping Kirishima up in a warm blanket. He placed his hand on top of his grotesquely bulging stomach and pushed down. Kirishima let out a soft squeal as two eggs came out, sliding one after another into a pool of merman cum. Bakugou let his hand up and did it again, another egg crowning. Kirishima sobbed quietly. 

He put his hand next to Bakugou's, feeling the eggs move inside of his bowels. He counted at least twelve of them, and his head dropped onto the sand. Bakugou's lips brushed his neck in a chaste kiss. "Stay awake," he hummed, pushing down on Kirishima's stomach, expelling more of his eggs. "If you fall asleep, they'll crack."  

Kirishima kept his eyes awake, despite exhaustion desperately trying to pull him under. An egg fell on top of his prostate and sat there for five seconds before skittering into the large pool of cum between his legs. He dug his heels into the sand as another scraped over the abused nerve bundle, whining softly as it caught on his outer rim.  

Bakugou released the pressure on his stomach so Kirishima could catch his breath before reapplying it. After several long minutes, all of his eggs were out of him, swimming in a pool of the merman's spunk. His dick, flaccid on top of his stomach, gave a final pulse. Pleasure sated his nerves, coaxing him into a deep slumber. Kirishima felt his body being tugged over the sand, but severe fatigue kept him from reacting.  

He passed out, waking up two hours later next to Bakugou on his nest of riches, his back laying on his chiseled chest. His tail stretched over the pile, coiling at the tip above the sand. Following the spiked and frilly appendage to his face, Kirishima blinked as Bakugou stared back at him, his eyes brighter than flames. "Did you enjoy your punishment?"  

Kirishima's body shuddered with the aftershocks of his brutal first time. Snickering, Bakugou flipped onto his back, bending his arm behind his head. "I know you did. You don't have to tell me, shitty-hair."  

Licking his lips, Kirishima tested his throat. His voice was raspy as he asked, "Will you let me go?"  

Bakugou seemed to ponder on the question for a moment, and his face broke away into a wide grin.  

"You're too good of a toy to let you go so easily. I think I'll keep you for a little while longer, at least until my heat is over."  

Kirishima dropped his gaze to the coins and gems he sat on. He was trapped down here because of them.  

Warm fingers lifted his head to stare back at Bakugou's smirking face.  

"Maybe this will teach you a lesson in stealing from a king."