"Jokes Are A Ladder, Yaomomo," Mineta said.
I was watching game of thrones and saw the chaos is a ladder scene between the spider and littlefinger and thought of this. Reminder that Mineta is the second smartest kid in class, only below Yaoyorozu:
"Camp town...sing this song...doo dah, doo dah..." Mineta murmured, perusing his locker for some unknown object. Momo could care less. She'd had quite enough of his ill humor.
Her shadow overtook him and he turned fast, a startle waving through his expression that was exaggerated beyond belief, "Yo, Yaomomo, what's good?"
"You and I need to talk, now," Momo stated flatly, her eyes darkened, "your behavior is completely unacceptable. Crass jokes, speaking in class, your disposition towards your female classmates-"
"Bro, you're fifteen. Stop talking like a noble woman from a medieval fantasy show."
"Are you even listening to me!?" Momo snapped. "How in the world did someone like you get into the top hero course? It baffles...it..." She paused.
"Cat got your tongue?" Mineta tilted his head.
"...It...makes complete sense," Momo whispered.
"Uh oh, she found out...something," Mineta shrugged. "That has yet to be revealed-"
"I've never seen you train...yet..." Momo looked away, thinking hard. "Ninth in the midterm without even trying. You didn't study..."
Mineta started bobbing side to side, "Hey look, Midoriya-San already does that weird murmuring stuff. We don't need a two point oh version."
"You spend more time making a fool of yourself than anything else. Explain."
"Explain what?"
"Explain how."
"...What is this, psychoanalyze the grape?" Mineta chuckled. Momo did not look amused.
"And during battle trials, when we fought Kyoka and Kaminari, you coated the walls with pop off rather than the entrances, allowing me to capitalize and put them both down..." Momo blinked in realization, "Kyoka-Chan would've assumed that you would place your grapes at the entrance and that's why she blasted through the walls only to meet your grapes...but you..."
"Oh come on," Mineta rubbed his neck, "it's not that complex."
"I thought you were improvising. But, you weren't."
"Mastermindneta, that's me-"
"Your jokes are not funny. They're stupid and repetitive and crude. Why do you keep making them?"
She took a step forward and gave him a study. Mineta was looking back with raised eyes.
"You have potential. You could be far more than...this. Your demeanor as it stands is completely worthless."
"...Worthless?" Mineta repeated and now he wasn't smiling at all. "You really think so, Yaomomo?"
Momo nodded, "It's beneath what you could become-"
"Jokes are a ladder, Yaomomo."
"W...What?"
Mineta's expression was focused then. Clear and calm. He looked at her directly in the eye. "Think about this: I stick like a little coward to a group of kids in the entrance exam. These kids are pretty strong and smart. They just so happen to know the exact way in which I can use my quirk. They fight the robots while I throw my grapes, that way, we all get points, right?" He shook his head, "no, only me, because only I stopped the bots. I think only one of them managed general studies. Sad."
Then he motioned at a perplexed Momo, "And then there's you. The sports festival, Tokoyami-San, you two square off for all of about ten seconds before Dark Shadow pushes you out of the ring. You wanna know why that happened?"
Momo stared at him, "Why?"
"Because everyone knows just how smart you are. You were born into greatness and are expected to be great. You got the wealth, talent, looks, a quirk everyone knows is awesome. You walk into a room and everyone turns their heads to see you."
Mineta directed a finger at himself, "Me? I rip sticky balls out of my head. I'm a dwarf. I ain't got no glaciers, fire, engines that make me go super fast, and no wind shifting punches. So, what do you think happens when people see me?"
Momo didn't answer. Instead, she watched him.
"They laugh, they get grossed out, or they just don't pay attention. I want that, Yaomomo. I need that. All I got is this," he tapped the side of his temple, "and a good cover."
"A cover for what? What exactly would you need to hide? Why not reveal your so-called intelligence and act like you have it?"
"Because, Yaomomo. Do you know how cutthroat this school is? I need every advantage in training I can get, otherwise Aizawa will send my ass packing. This brain right here is the only advantage I got and if I reveal that trump card then I'm just another smart kid instead of that silly little guy in class A who just barely sticks to the requirements like a good little underdog."
Momo had her brow furrowed and thought deeply once more. She crossed her arms, "Why are you telling me this then? Why not keep up the charade?"
"You saw past it," Mineta shrugged, "you're probably smarter than me, I'll give that one away. But...do you really think they'd believe anything about this?"
"...No."
"Of course they wouldn't. But...since you know. Maybe you'll find something I've figured interesting."
"And what would that be?"
Mineta raised a finger, "Isn't it weird to you how Midoriya-San is so strong and powerful to the point that his own body breaks from it?"
"He was a late bloomer. He said so himself. What's your point?"
"Stay with me. He gets his quirk late and it just so happens to be really similar to another power type quirk. All Might's. Then, All Might just so magically happens to become a teacher here and he takes a special interest in Midoriya-San. Really coincidental, don't you think?"
"What do you think?" Momo questioned
"I got a theory. In some shape or form, Midoriya-San got All Might's quirk and they're keeping it a secret."