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30,000 Kelvins

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“Denki?” Momo whispered, pushing open the slightly-ajar door to his dorm and peeking inside.   

It was dark and messy and quiet, and Momo realized with a sting of disappointment that the lack of a response meant she was talking to an empty room. She should have known – Denki could never sleep through a thunderstorm. It was the electric charge in the air, he said, that kept him awake. Momo could only imagine. Sleeping through flashes of plasma raining from the sky and shockwave expansions of superheated air was one thing; sleeping through the feel of your skin prickling with your Quirk (that, Denki said, was simultaneously the best and lamest description he could come up with), was something else entirely.

It was definitely the thunder and the lightning that had Momo, for one, up and about now, long before her alarm could even think of jolting her awake with a spike of adrenaline. It sounded rather unpleasant when put that way – and, even considering that she was accustomed to the sensation, it still was.

But she almost preferred it to fearfully sneaking around at 4:30 in the morning in desperate search of her missing “thunder buddy” (damn Denki and his labels).

Maybe he’s in the common area? Momo thought hopefully, padding quietly down the stairs. He could’ve been anywhere, she wouldn’t have cared, as long as it wasn’t outside. Outside was the last place she wanted to go during a thunderstorm. Outside, her chances of being struck by a stray bolt were much larger than in the safety of an insulated structure.

The common area, much like her friend’s dorm, was dark and quiet and empty. Momo’s heart sank. “Denki?” she called just in case, heading for the double doors in the front. He was outside, she already knew. Outside was the only logical place he’d be. Because Denki.

The room was briefly illuminated with a painfully bright flash of purplish-white, and she involuntarily flinched away from the resounding crack of thunder that followed. Astraphobia was such a stupid and irrational fear to have, especially for someone like her. The chances of being struck by lightning in her lifetime were, while not extraordinarily low, minimal – enough so that she’d never encountered someone who’d fallen victim to the rage of the skies in her meager years.

But it certainly didn’t help to know that the chances of winning the jackpot were drastically lower, and her family did personally know somebody who had done just that.

“Denki?” Momo called, louder, into the chilly wind that blew through the open door. She paused, hesitated, straining to hear even a shred of his voice. When the air around her didn’t immediately explode with sound and fire, she cautiously closed the door behind her. Where was he? “Den-”

“Hey, Momo.”

Momo’s skeleton threatened to emancipate itself from her skin, heart and stomach lurching into her throat and strangling her scream as it was born. She landed on her feet, at least, as she spun to face the perceived threat, and dropped into an ingrained, defensive stance.

It was Denki.

“Oh. Denki,” she said, voice curt with embarrassment as she straightened and walked over. He was sitting against the wall a couple of meters to her right, wrapped in a dark blanket. He was snickering as he opened half of the blanket for her, and continued as she sat down next to him, miffed, and pulled her knees to her chest. “Geez, Momo,” he giggled. He had a cute laugh. It made him sound forever young. “I swear, you jumped higher than Tsu!”

Momo huffed. “You scared me, Denki!”

“Yeah, no shit.” An unseen bolt fleetingly lit the sky in flickering brilliance, and Momo pulled the blanket tighter in spite of herself. Denki, as per usual, seemed unfazed. “Dude, you’re fine,” he said lazily, draping an equally-as-lazy arm around her shoulders and patting her knee with his other hand.

Denki was one of a handful of her classmates who was aware of Momo’s astraphobia – and, frankly, she had assumed that he’d be the last person out of those that she would seek out for comfort during a storm. He was loud and obnoxious and a hormonal teenage boy (read: girl-crazy), but there was something oddly comforting in the knowledge that he had some (albeit meager) measure of control over elements like these, even on a much smaller scale.

He was abnormally quiet this morning, watching the storm roll in. Usually he’d be trying to make conversation by this point, trying to distract Momo from her fear. She had thought it a sweet but mildly annoying gesture up until today. What was on his mind, she wondered. “Please tell me you have some way of regulating your charge,” she muttered instead, shuddering when she noticed how the hairs on his arm stood slightly on end. Oh, crap, she hoped they weren’t about to get struck (never mind that they were under a porch). What if Denki wasn’t smart enough to –


Momo sighed tightly. Maybe seeking him out today had been a bad idea, seeing as how he was sitting outside, relatively exposed to the elements. As unpredictable as his Quirk was, it would make more sense that Denki didn’t know how to regulate his own electrical charge any better than anybody else. In fact, he probably barely even knew what an electrical charge was in the first place. “Your electrical charge,” she stated, patiently. “So, lightning is caused by –”

Oh! Oh, my electrical charge!”

Momo pursed her lips. “Yes.”

“Oh, yeah, yeah, okay. Yeah, don’t worry about it. I already took care of it.”

Momo hummed doubtfully, and then stopped short. “Took care of what?” she asked, turning to look at Denki in mild confusion.

He gave her a look. “My charge. I’m keeping it negative. Isn’t that what you were worried about?”

Momo was silent, and gaped at him in the darkness. Lightning strobed across the sky, and this time she did see the bolt in her periphery, the harsh light hardening even the softest features of his face. Even after it had faded, something foreign remained in his expression, barely illuminated by the warm glow of the lampposts along the path to the dorms. “Yes, right,” she said quietly, looking away.

Since when had Denki even had a vague idea of how electricity worked?

The roll of thunder that followed was deep and long and powerful, rattling the windows in their frames, and it sounded to Momo entirely more ominous than any of the others in the storm. Denki removed his arm from her shoulders and nudged her as she shrank further down into the perceived safety of the blanket. “Chill, Momo, it’s just sound,” he said, almost teasingly.

Momo nodded, wringing the blanket in her fist.

So he was familiar with how lightning worked. That was new – she seemed to remember him failing his last physics exam relating to electricity. In fact, she knew he had, because Bakugō had laughed and laughed and made some highly offensive joke about it. Denki had laughed with him, of course, because that was just what Denki did. Maybe he’d actually been insulted by it, she decided. Maybe it had just prompted him to study. That was probably it.

But as underdeveloped as her instinct was, far behind the level on which her brain practically functioned, she still couldn’t shake the sense that something wasn’t sitting quite right. Not entirely wrong, but uncomfortably askew.

“You know, Momo, I’ve always wondered,” he said after a while. Gentle rain had begun to fall, and the clouds were dimly glowing a deep, saturated blue in the dawn above. Though the thunder had thinned considerably, the occasional peals that still roared out were quite loud and close, vibrating the building around them.

Denki was warm, and Momo pried herself up from where she’d melted sloppily against him, cheek stiff from where it had been comfortably squished into the softer part of his shoulder. “Yeah?”

“Why do people automatically assume you’re unintelligent if you don’t perform at ‘optimum capacity’ in school?”

Momo tensed, only half from the sputtering flash above the dorms. It crackled harshly after several seconds of silence, and she resisted the urge to cringe into someone who suddenly felt very much like a stranger. Her eyes darted over to him; he kept his gaze leveled firmly on some invisible anchor ahead.

In all the time that she had known him, Denki had never once sounded bitter.

The shards of sharp ice in his voice melted into a cold slush in the pit of Momo’s stomach. They didn’t seem to be directed towards her, at least, but rather something (somethings? Someones?) out in the world beyond. Now her instinct was screaming at her that there was something… wrong in the way his eyes were hard and his brow was furrowed and his jaw was set. Something was wrong with Denki. And what was worst was that Momo had no idea how to help him.

That sort of helplessness, in some way that she couldn’t quite put to words, hurt.

Denki’s eyes finally danced over to her, and Momo remembered that he’d asked a question. His face looked inexplicably foreign, like earlier, and it formed a lump in her throat. She swallowed it down alongside her internal storm. I don’t think you’re stupid, she wanted to say, but the words caught halfway to her mouth. It burned to realize that they would have been a lie. It was common knowledge that Denki wasn’t the sharpest tool in the shed. Just because he had a way of making everyone he met fall in love with his personality didn’t mean he was smart.

But there was an inkling of Momo, buried deep, that was just beginning to wonder.

“I don’t know” was what she ended up saying, softly, avoiding his gaze. Why, she wanted to ask, but left it at that.

Denki looked back ahead.

Dangerous, hypervigilance warned. Now that was just a false alarm. Momo supposed it couldn’t be helped. She already felt responsible for the well-being of her class as vice rep as it was; she was bound to be a little overcautious, especially taking into consideration that she’d survived too many villain attacks already. Not to mention, there was still the traitor to find at UA, who was still at large.

But Denki? Dangerous? That was rubbish. Powerful, yes (perhaps even powerful enough to defeat Momo), but nowhere near smart enough for that power to be a threat… right? Momo leaned back against him, because he was warm and sweet and even though he felt so horribly off and tense he was still Denki, and Momo loved Denki. He was her friend. He was her thunder buddy.

The next flash of lightning was blindingly solid, washing the world into an alien landscape with its harshness from the clouds above. Momo’s heart didn’t even have time to beat twice before the crackling began, and then the thunder exploded like a bomb in all its terrible glory. The windows rattled so hard that some very ridiculous part of her feared they would crack, and even the floor beneath them vibrated in the wake of the shockwave. Momo squeaked and was digging her fingers into Denki’s bicep almost before she was aware of it.

That had been close. Way too close.

Denki didn’t even twitch.

Hypervigilance resurfaced and began questioning the true capabilities of his Quirk. Momo couldn’t quite bring herself to ignore it this time.

It was not long afterward that the lights in the common area switched on, shining onto the porch through the windows. Iida must finally have decided to get up (he hadn’t seriously slept through all that, had he?). Denki gently pried his arm out of Momo’s grip and stretched. “Welp, guess that’s our cue to go inside,” he said. His voice didn’t sound quite so hard as it had before, and it eased the quiver in Momo’s gut slightly.

He stood, pulling the blanket up with him, and extended his hand down to her. Her fingers were trembling when she took it, and she cursed her astraphobia for what had to have been the fifteenth time that morning. “Hey, don’t worry, Momo,” Denki said, gently tugging her to her feet. He paused, studying her. “Didn’t you say that thinking up random facts made you feel better?”

Momo flushed. It was stupid but true. “Yes…”

“Okay, I’ve got one.”

She fixed him with a dubious look. “Well?”

Denki grinned. “Did you know that the air lightning passes through can get as hot as 30,000 kelvins, which is also around 30,000 degrees Celsius or 53,500 degrees Fahrenheit?”

Momo scowled and slapped his arm as he giggled his adorable laugh.

She couldn’t think quite straight for the rest of the day. Ω