Devil Fruit System in MHA

Kai sat near the back of the bus, headphones on to drown out the chatter. Class 1-A was abuzz with energy, everyone eager for their rescue training. He stole a glance at the heroes accompanying them—Snipe, relaxed but alert; Ectoplasm, stoic and imposing; Eraserhead, bundled on the floor in a disgustingly colored sleeping bag; and Nezu, radiating his trademark mix of cheerfulness and unsettling intelligence.

Kai looked around at the students near him, Midoriya in the Aisle seat to his right, Shinsou and Uraraka across the aisle, Iida and Tsuyu in the seat in front of him. Over the din of his music, he managed to hear someone call his name. Midoriya was making small talk with Uraraka, and the blush on his face never went a shade below pink. Shinsou seemed to be asleep.

"Dude, what are you listening to?" Kaminari asked, leaning over the back of Kai's seat and putting his face right between his and Midoriya's.

"Classical for now." Kai said, pulling one earbud out, revealing a luxury pair that Kai had made himself with the Tinker Fruit.

Kaminari seemed puzzled. "Like… Mozart? Bach?"

Kai smirked and checked his phone. "Vivaldi, currently."

"Huh. Cool. Can I listen in?" Kaminari asked.

Kai shrugged. "Sure, I don't care." And he handed Kaminari one of his earbuds, a gold trimmed earbud that fit perfectly in the ear, and Vivaldi's Winter played in Kaminari's ear.

"Huh. I kinda vibe with this." Kaminari said, nodding along.

"Yeah, it's good a good song. So what did you want to talk about?" Kai asked, knowing Kaminari had a motive to speak to him.

Kaminari offered a faint, awkward smile, but climbed over the seat and landed in between Midoriya and Kai.

"So I wanted to know why the principal is taking you for quirk training himself." Kaminari said, blushing a bit as he settled in. "I know it's rude to ask, but I got curious."

"Nah, it's natural to be concerned. The answer is that I'm Nezu's personal student, and he figured that since Snipe and Ectoplasm had the day off then they could benefit from more specific aspects of my quirk."

Kaminari furrowed his brow. "But isn't your quirk energy absorption? I remember you being there at the QAT."

Kai winced. "Well, recently I've had a trauma-induced Quirk Awakening, and the effects can be as volatile as they are powerful. I really can't say more, it's classified."

The last part was a lie, and even if it wasn't, 1A had signed Non-Disclosure-Agreements on anything they learn about teachers and other students' quirks and personal lives, to protect the underground heroes, both present and future.

He was just too lazy to elaborate so he used the story as a cover.

Kaminari flinched. "Ah, my bad. I shouldn't pry. I have another question though. Can we work on my Quirk after school? Midoriya said that you've been really helpful in learning control and my quirk has this massive drawback if I overload my brain."

Kai shrugged. "I don't see why not. I'm already booking a gym to help Midoriya and Shinsou, although the latter is mostly exercise. You can just ask one of them when we're meeting and they'll update you, or you can give me your number and I'll text you."

Kaminari sagged in relief. "Thanks man. The whole overloading thing really weighs on me. I'd relish in the help."

"No problem." Kai said, but internally he was celebrating. He'd just roped another one of 1A's students into his little study group, and it was one of the ones he wanted most. He already had a few inventions to help Kaminari, depending on how his quirk worked.

Soon, Vivaldi's Winter soared to its electrifying crescendo, then faded into silence. The next song bursts forth with a deep, driving bassline and smoldering, almost sinful vocals. Kaminari's jaw dropped; his shock palpable as the elegance of Vivaldi gave way to the sultry chaos of Sam Smith's Unholy.

Kai chuckled. "I'm not a one-track kind of guy. This playlist has over three hundred songs, covering just about every genre you can imagine. Granted that it's pre-quirk. I don't appreciate most of the new stuff, it's better if it's unaided by quirks, you know? There's a difference between a song someone made by hand and someone using a composing quirk."

Kaminari just let the song flow over him, apparently never having heard it before. "Can I get the playlist link? I want to give it a better listen later."

"Sure. Give me your phone."

A minute later, Kaminari was looking at a contact in his phone labeled "Apostle of the Rat God".

Kaminari raised an eyebrow. "What's with the contact name?"

Kai just shrugged and gestured at the Principal of U.A. who was chatting idly with Snipe.

Kaminari looked at his phone and saw a link to a playlist titled CHAOS surrounded by flame emojis.

Kai and Kaminari continued their conversation about music until Kai heard Tsuyu say a sentence he'd been anticipating.

"Isn't your quirk a lot like All Might's?"

"U-uh I-I have no idea what you mean!" Midoriya frantically denied, waving his arms in front of him.

Shinsou spoke up from behind Uraraka, apparently startled awake by Izuku's sputtering. "I mean the power is similar, but All Might doesn't shatter every time he sneezes."

Iida looked appalled. "Shinsou! That kind of comment is unbecoming of a U.A. student! While I do agree that the comparison is lacking, you don not need to demean your classmate in the process, especially in front of a member of another class!"

Shinsou rolled his eyes. "Chill out Tesla Calves. At least Midoriya has a quirk suitable for heroics. Something big and flashy, so that he can draw the most attention."

Midoriya immediately started rambling and pulled out a notebook with a purple cat on it. "But your quirk is so cool Shinsou! While your quirk isn't an enhancement type, it's still borderline overpowered for control and combat situations! You could use your quirk to-"

At that point his speech became unintelligible, even for Kai.

Kirishima interjected, sitting in the seat behind Uraraka and Shinsou. "Like Midobro said! Shinsbro, your quirk is useful in so many situations! You can use it in ambushes, hostage situations, and straight combat. Honestly, I'm a little jealous. My quirk is only useful for taking and doling out hits."

Midoriya seemed to mutter even faster, his words tumbling over one another as he swapped his Cat notebook for one with a cover designed like a brick wall.

"Your quirk is so awesome though! It might not be flashy, but it's easily top three in defense! I imagine with enough training, you'll become impenetrable, although probably losing speed as a side effect, but you can negate that with—"

And then, as usual, his muttering turned back into an indecipherable blur.

Kirishima perked up, his grin widening. "Thanks, Midobro! I'm glad you like it so much. I just wish it was as flashy as Inasa's or Yaoyorozu's." He scratched the back of his head, looking slightly embarrassed.

"I get it," Kai said from the back, chiming in to break the awkward silence that had settled. "But sometimes being unassuming is what makes a quirk so powerful. You don't need to be flashy to be effective. After all, Crust is the number eight hero, and you're super similar to him." Kai said, and leaned back in his chair. Almost as an afterthought, he added, "You remind me more of Crimson Riot though."

Kirishima got really quiet. "You think I'm like Crimson Riot?"

"Yeah," Kai said with a small nod. "He was known for his raw, straightforward strength, but what really made him stand out was his resolve and energy. Just like you."

The bus grew quieter again as the words settled in. Kirishima seemed to swell with newfound confidence, almost as if the praise had been the exact fuel he needed.

Kirishima sat back with that, smiling lightly. "Thank you, Kai. You have no idea what that means to me."

A quiet settled over the bus for a few seconds until Sero said from behind Midoriya, "If we're talking flashy quirks, then we have to mention Bakugo!"

Tsuyu considered the point. "Yeah, his quirk is really strong. It's a shame his personality is so bad."

"FUCK YOU FROGGER MY PERSONALITY IS FUCKING PRISTINE!" Bakugo shouted.

Kaminari nearly doubled over in laughter, clutching his stomach. "See, Kai? It's been a week, and we can already tell his personality's like raw sewage."

Kai barely spared a glance at the commotion, his tone dry. "That's rough, buddy."

"Damn." Shinsou said. "The toxicity is strong in this one."

Kai tuned out the ongoing fight between Bakugo and common decency and just watched the USJ approach from the window, the lively beats of Duke Ellington laying over his earbuds.

 ~~~~~~~~~~~~~~~~~~~~~~~~~~~

Kai stepped off the bus last and came into the scene of Midoriya and Uraraka fanboying hard at the sight of Thirteen. He slid next to Nezu and started whispering to the rodent.

"Yo, where's All Might. I don't see him."

Nezu chuckled. "I assure you, Kai, he'll be here. He may be running a little late, but he will arrive. Have you always struggled with anxiety?"

"Nope. Just since my parents died brutally."

Nezu visibly recoiled. "Ah. I see. Have you seen a therapist? If not, Hound Dog specializes in Trauma and his door is always open."

Kai exhaled a tense breath. "Sorry for lashing out. I'll take you up on that and see him later. I promise."

At this point the Entirety of Class 1A had already funneled inside the USJ, Thirteen having already finished their speech. 

"It's fine Kai, it's my fault for the pointed question. Let's just go inside and get our training started."