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30 days of writing (not always drabbles though)

Chapter Text

Rui takes his glasses off, pinching the bridge of his nose. He’s more than tired already for having to work in the later hours. He thought that being a scientist used to be cool and all, learning knowledge that has been passed down from scientists of the past, discovering every little new thing that gives him excitement and amazement in his eyes. He still does, but work seems to have made him lose that excitement of his.

Checking the time, Rui sees that it’s 8:45PM by now. This is quite late for almost everybody, including the janitor, to want to stay in the lab. While stretching his body, Rui is thinking about going home for a nice snooze and cup of tea until he hears the sound of glass tapping and he swivels his chair to turn to look at a dark-haired man named Byou inside a tank filled with water, who holds up his whiteboard asking him “Are you tired?”

Then Rui smiles, leaving his chair and picking up a small whiteboard and marker pen in hand, going towards the giant glass wall separating between them air and water, a human and a merman (not really per say, in Rui’s opinion. Byou’s just a human who has the capability to breathe underwater for long periods of time before resurfacing for air, similar to past mammals like dolphins, seals and whales). He wears nothing but a speedo legskin for practical purposes such as for research and for decency’s sake.

Rui thinks that’s because he looks good in one and a lot of the female staffs and several male staffs (including himself) are guilty for ogling at him.

“Yeah, paperwork sucks,” he wrote on his whiteboard in reply as he shows it to Byou.

“I feel you,” Byou grins, and Rui grins back in return.

Truth to be told, Rui has never told anyone that one of the reasons that he tends to stay behind at the lab is so he can talk with Byou without interference. Granted, he does do so too when other scientists are there, but only to ask some questions that Byou sometimes think is boring when he tells it to Rui later.

Nobody actually told Rui that talking to the merman is prohibited, there’s no such rule since no one knows if the merman can talk, but neither does Rui want anyone to know that he is doing that for some time already, so this is a little secret between him and Byou, for Byou keeps him company when everyone else left and it makes sure that the merman would not feel terribly isolated and lonely from being in the tank.

“I miss the outside world,” Byou wrote on his sign, which surprises Rui. Months of being with the merman had given no hints whatsoever that Byou is homesick, then Rui remember what “going outside” meant.

“Isn’t it unsafe to go outside?” he has written. “You’ve been here for months, so surely your body wouldn’t adapt well once you leave somewhere as sterilised as this?”

There were a lot of words crammed into the whiteboard so the size of the words is smaller than usual, but still readable for Byou.

“Maybe so, but I got friends out there. They’re probably already thinking that I’m dead or a tortured science experiment.”

This worries Rui, a lot. At best, they’ve probably sent in a threatening letter telling them to let Byou go, or worse, break in and harm everyone in the building. At the same time though, he finds it hard to imagine letting Byou go after months of talking to him. His face must have shown what he thought about it because Byou is rubbing off his previous dialogue and wrote down something else.

“Meet me at the top of the tank.”

He gives Rui no time to reply back, already swimming up towards the top and waiting for him. Having no other choice, Rui turns towards the ladder that leads to the top of the tank, the area where others like him volunteer their time to bring food to feed Byou.

As soon as he arrives on the platform though, he almost fell off the edge when Byou starts talking. “Now this is a better place to talk, Rui.”

“Y-You can talk?!” Rui gawks before quickly composing himself. “Wait a minute, if you can talk this whole time, why didn’t you admit it in the first place?”

“Well, when you’re submerged in water all the time and having a glass wall between you and me, it’s easier to just not talk,” he shrugs. “And you guys never asked if I can.”

“Oh,” Rui blinks as he tries to accept the fact. It makes sense as to why Byou doesn’t talk at all even through months of written communication. However, it makes Rui feel dumb for never having done that, much less try to.

“Want to take a dip with me?” Byou suggests.

Rui hesitates.

“I don’t think that’s a good idea.”

“Relax, it’s clean I promise. I use that toilet for a reason. I may live underwater but I still do my business out of it, and I live in a tank.”

“But I’m in my clo—“

“You can just wear your underwear if you want to. Not like I’ve never seen a penis before,” Byou says. “Besides, I’m not that stupid to know why you guys made me wear this cool looking legskin for nothing. I have to admit, it accentuates my legs.”

Hearing that, it’s hard for Rui not to roll his eyes so hard, and decided what to do. Taking off his clothing one by one, folding them up and keeping them somewhere far from the edge of the water, Rui is surprised as to how warm the water is when he steps in from the ladder. Swimming towards Byou, he asks, “Don’t you get tired staying in the water all the time? You could’ve just got out of it once in a while.”

Byou looks at him face to face, which Rui secretly admits that he looks good even out of water with his hair sticking to his face, swimming a bit closer towards Rui, and says, “I can get out of the water when I want to, but I can’t imagine getting tired being with you.”

When Rui pulls Byou into a kiss, he thinks of how much of an idiot he is for not immediately jumping into this. Byou pushes them slightly towards the metal ladder so that they will keep afloat while making out. It doesn’t feel wrong, nor does it feel right. To Rui, it’s straight out lust and desire right now.

“I can’t… imagine getting tired of you, or even see you gone from me,” Rui says when they pull away, a bit breathless and panting.

"Me either," Byou says, this time pulling Rui into making out again. Knowing that he has one arm wrapped around Byou's neck, Rui uses his free hand to grope Byou's crotch, feeling his cock getting hard and big, stretching the latex surrounding it. Byou is right in saying that the legskin accentuates his legs (and butt), but damn does his cock look good in latex too, even if Rui wants that out of the fabric to see what it really looks like. From what he can tell and touch, it's not a disappointment.

"I want your underwear off," Byou whispers to him as he moves his lips from Rui's lips towards his neck, nibbling and licking but not biting. Nodding, Rui pushes himself back to the ladder so he can stand on one of the steps whilst taking off his remaining clothing and left it on the platform.

Now naked in front of him, Byou takes in the sight of Rui. His skin is pale, his cock is quite well formed in its hardened state, and his thighs are like a temptation. Byou has already seen his tattoos but he still looks fascinated by them. The tattoos don't look out of place for someone as cute as Rui.

"So how do we start this?" Rui asks nervously, a bit not sure what to do while Byou takes interest on his body. The merman smirks, gently coaxing him to let his body go down to the water until Rui is submerged at least by waist deep.

Dipping his head down into the underwater, Byou gives his cock some long licks from the shaft to the tip of the head while his left hand busies itself on fondling his balls.

Rui holds back a moan when he sees Byou taking his cock into his mouth. Getting a blowjob is not something Rui has never done before, but getting it while underwater by Byou is something new, and he seems to know his way in pleasuring people with his mouth.

"Byou-kun...!" Rui gasps when he feels the tip of his cock bumping into the end of his throat. Byou looks up at from the water, giving him a dirty look that hints to Rui that there's more to come. And there is one already coming, when Rui feels a finger circling his entrance before it pushes in, with Rui trying his best to relax his muscles to let it in.

With water as the only source of lubricant, it's not exactly comfortable having a finger thrusting inside of him, much less so when Byou introduced a second finger after a few thrusts. Whimpering, Rui grabs Byou's hair and grips onto it. Sensing Rui's pain, Byou pulls his mouth off of his cock and comes back up to the surface.

"Is it hurting you?" Byou asks, worry clearly evident on his face.

"Yeah," Rui bites his lips. "Just give me some time."

It takes some time while Byou gives him fluttering kisses to ease him up before he starts pushing his fingers in and out of Rui, the digits rubbing against the walls until Byou finds that bundle of nerves.

"There!" Rui yelps, pulling himself closer to Byou. Playing with his prostate by touching and rubbing against that spot, it doesn't take long for Rui to be groaning at the loss of the digits and replaced by a much bigger than the fingers to be inserted into him. Rui did not noticed or know when Byou pulled his legskin down to let his cock and balls out.

"Ready?" Byou asks first, looking at him to be sure that he is.

"Yes." After saying that, Byou pushes past the ring of muscles and carefully slides in. He gives a few small thrusts just to test the waters.

"How is it?" he asks. Rui winces at first, which worries Byou, until he smiles.

"Good, but it would be better... if you go in a bit deeper."

Taking that as a cue, Byou alters his moves until he thrusts in a bit deeper each time, a little faster, enjoying the sight of Rui pinching and flicking his nipples occasionally (especially his right one, Byou takes note). Eventually he manages to push his cock with ease, the speed and strength of his fucking now fast and hard, and Rui moaning and groaning his name out loud that he has to kiss him to keep his voice down from being heard by anybody walking by the hallways.

Now full on fucking Rui in the water against the railing, Byou puts his hand behind Rui's head as a precaution just in case he knocks Rui against the ladder too hard. Rui, in the meantime, tries to keep his voice down, even though the pleasure he is receiving makes it difficult to do so while remembering to hold onto the railings to avoid slipping into the water. As much as he enjoys this, he remembers very well that Byou's tank is over 7 meters tall and that is very likely to drown him, which is not very hot and not a good idea to forget that.

Feeling a familiar tight coil on his abdomen, with Byou's hands too preoccupied with making sure that his head doesn't get knocked against the railing and his other hand gripping onto his hip and this feet on the steps to keep his thrusts on sync, Rui takes the risk to take one of his hands off the railing to stroke his neglected cock. A rational part of his mind keeps pestering him that he'll have to clean and change the water up if he cums in the water, then the sex-addled part of his mind tells him that he can have sex with Byou out of the water if he does that, and the thought of getting fucked again helped push Rui over the edge. He screams in pleasure as he reaches his climax, spurts of his cum shooting out of the water like a spectacle worth watching.

Byou follows soon after, giving a few more hard thrusts while kissing Rui to muffle his moans instead as he spills his semen inside of his lover, filling him up.

Now falling into a post-orgasmic bliss, they make out in a lazy way, tongues touching and lapping against each other. Their hands hold onto each other, one of them having prune-like skin and the other has firm, calloused ones. The dark-haired merman is giving Rui slow, gentle thrusts, as if he doesn't want this to end yet.

In Rui's opinion, this is one of the best sex he has ever had in his life so far (other than a bruised back) and it is definitely going to be fondly remembered. His brain feels like jelly although he keeps reminding himself that he has to waste his night cleaning and sterilizing the water up to hide the evidence of their tryst. Still, there's that out of the water thing...

"Hey Byou-kun, are you up for a second round while the tank gets cleaned?" Rui asks, grinning in such a silly way that Byou think it's cute.

"Hmmmm... How long does it take for it to clean up the tank?"

"About 3 hours."

Smirking, Byou pulls out of him and says, "I can fit in one more round if you're up for it."

"I got a bottle of lubricant by my desk drawer."


From then on, well... by day, Byou's a subject from the outside world to be researched for the potential to survive and thrive in a harsh environment and Rui is another scientist checking him out from time to time, asking him questions through the portable whiteboards and marker pens. By night and when everyone else is gone, they're lovers who make love or fuck hard with lust and desire in mind, or both. Merman and scientist by day, lovers through and through by night.

As long as this is kept as a secret between them, the knowledge of their newfound relationship is out of bounds from everybody else for now.