Chapter 53: Less Talk, More Thighs! Mt. Lady's Secret Manual!

Aaah... home sweet home. Or, well, that's what I'd say if this were actually my house.

Izuku tilted his head curiously in front of the picture hanging on the wall.

Why does an adult hero have a portrait of a cat in her living room? No, better not to ask. In this house every answer comes with a new problem stuck to the back of it.

"I don't get how the hell I ended up mixed up in all this!" Yu exclaimed, jabbing an accusing finger at Nemuri while awkwardly leaning on her crutch. "This is all your fault, Kayama! I was living my life just fine and then you show up to turn it into a disaster!"

Nemuri, comfortably reclined on the huge couch, had a bandaged leg propped up on a cushion. Instead of looking guilty, she smiled with total calm.

"Oh, come on, sweetheart. I don't recall forcing you into that hospital room."

Yu narrowed her eyes.

"That's not the point!"

"Oh, no?" Nemuri let out a small laugh and continued. "Because, if I remember correctly, you walked in there of your own free will. Crutch, drama, and everything."

"Could you stop saying it like that?!"

"Say what?" Nemuri's smile got even wider. "That you got yourself into trouble all by yourself?"

"I didn't get myself into trouble! Trouble found me!"

"Sure, sure." Nemuri let out a little giggle. "How convenient, Mt. Lady."

"Don't call me that when I'm mad!"

Yu clenched her teeth, her face twisting into a scowl of frustration that Izuku recognized as the prelude to an explosion. But her response didn't come in time, and Nemuri used the silence to stretch her bandaged leg with an elegance that bordered on provocative.

Gotta admit, Nemuri-sensei looks really attractive when she does that, Izuku thought, looking away so he wouldn't end up staring like an idiot. It's like watching someone rub salt into a wound with a smile.

The reason the three of them were there was simple to explain and horrible to say out loud. They'd already been discharged, and a procedure like his couldn't exactly be carried out in the middle of a coffee shop without ending up on the evening news. The home of the adult hero herself was, by process of elimination, the only place on the planet where groping a professional could pass for something almost respectable.

Well, it's not like I could just go home and grope her chest in front of Mom. Ugh... No, what a terrible idea! GET OUT OF MY HEAD, INTRUSIVE THOUGHTS!

"Ahem... ladies," Izuku raised a hand with all the formality he had left after the week he'd been having. "Could we, uh... get to the point?"

Yu dropped down onto the other end of the couch, adjusting the sling on her left arm, and shot him an annoyed look.

I still can't wrap my head around how I ended up here. A regular kid, in the living room of an adult hero, with the noblest mission in the universe: touching Mt. Lady's chest...

Izuku lowered his eyes to the floor for a second, weighing the idea.

Though, come to think of it, if I actually said something like that, I'd end up under the foot of a twenty-meter woman. And I'm not into feet... Now, dying crushed between a pair of giant thighs, that sounds like something else entirely, heh heh...

"Izuku." Nemuri's voice snapped him out of his trance, one eyebrow arched. "Why does your face look like you're thinking about something bad?"

"Ahem, ahem!" Izuku straightened up. "You know how it is, sensei, I was just thinking about how my Quirk could, uh... improve the world of heroes. Y-yeah, that's it, improve the world of heroes, which is my noblest and most selfless goal."

Nemuri sighed and rested her cheek on her hand. She knew perfectly well that the kid most likely had his head full of nonsense, and after understanding how that particular Quirk worked, she'd stopped fighting with that reality. If dirty thoughts helped Izuku read the manuals better, the world could take care of the moral side of things.

"Well then, I'll leave you two alone so you can grope Yu." Nemuri stood up, leaning on the armrest. "Be gentle with her, sweetheart, she's inexperienced."

"Sensei, if you say it like that, it can be totally misinterpreted!"

"INEXPERIENCED?!" Yu snapped, and for a second her crutch threatened to go flying. "I've got more field experience than half the pros in your ranking, Kayama!"

"I didn't say what I was referring to, sweetie." Nemuri answered with a calm that only served to fire Yu up even more. "You're the one who filled in the blank."

"Because with you, nobody ever knows what the hell you're insinuating!"

"And where would the fun be if it were that easy to guess?"

Yu let out a growl, clearly about to start another argument.

Izuku gave Yu a couple of pats on the back before the situation escalated toward a second hospital visit, and helped her get settled more comfortably on the couch.

"Miss Yu, please calm down. I know this is a little embarrassing for y..."

Yu raised a finger and pressed it against his lips, shutting him up.

"You already explained how this works. Don't make it more complicated than it needs to be. Just do what you have to do."

Izuku swallowed and nodded.

"...Yes, ma'am."

Yu huffed and muttered:

"And stop calling me ma'am. You're making me feel old!"

Yu clenched her teeth and closed her eyes, bracing herself for what was about to happen. Izuku admired her for a second for the way she faced the matter so directly, and silently thanked the fact that her attitude wouldn't stop him from testing his precious chest theory on Mt. Lady herself. He brought his hands up to the hero's generous bust with total anticipation.

But Yu stopped them halfway.

"W-wait! I c-can't..." Her teeth were clenched and her face was red. "Ugh, this is harder than I thought. You said it works on padded areas, right?"

"Uh, yeah, but..."

"Then do it on my thighs!"

"H-huh?!"

"Yeah, my thighs." She let go of his wrists and crossed her arms over her chest, looking toward the window. "I'm not ready for, you know, letting some weird kid touch me up there."

"Weird? But that's how my Quirk works, it's not like I invented it."

"That's exactly why I said weird." She shot him a sidelong look. "Less talk, more thighs, Midoriya."

Great. I haven't even started and I've already got a bad reputation in this house. Way to go, Izuku, a round of applause for you.

Izuku sat down beside her and slid his right hand along the surface of Yu's thigh, warm and surprisingly firm, with a softness that gave a little under the pressure of his fingers.

T-THIS. THIS HAS GOTTA BE A DREAM. I fulfilled my life's goal! Who'd have thought I'd go from being a nobody to being a nobody who gets to touch the thighs of professional heroes. Mom, look at me and be proud of your son... ahem, forget it, better if you don't look, this probably looks pretty embarrassing from the outside.

After a few seconds without seeing the manual, Izuku started to get a little alarmed.

That's weird, nothing's showing up yet.

He moved his hand up a little higher, tracing the curve of the thigh toward the inside, and Yu tensed as she felt his fingers advance.

"H-hey. Is that necessary, or are you just taking advantage?"

"Both." Izuku paused for a second. "I mean, no. It's necessary, I swear. The manual doesn't show up until the connection is more... hmm, I don't really know how to explain it well. The softer the area, the stronger the reading. Does that make sense?"

"That sounds like something a pervert would say with a well-prepared excuse."

"I didn't design it, Miss Yu." He slid his fingers a little further inward. "That's just how this thing works."

Yu accidentally clenched her thighs and trapped his hand halfway, leaving him immobile between two surfaces that had no intention of budging.

"...Ugh." She closed her eyes, uncomfortable with the whole situation. "F-fine. Keep going."

Izuku kept slowly rubbing the inner area, searching for the point of contact that would trigger the reading, and just when he thought he was gonna have to give up and ask her to let him touch her chest, the lines of light bloomed in the air.

[QUIRK ANALYSIS INITIATED]

NAME: GIGANTIFICATION

USER: YU TAKEYAMA

RELATED PHYSIOLOGY: The Quirk multiplies body volume and mass through an accelerated growth factor, scaling the entire physical structure proportionally. Bone, muscle, and circulatory system expand in tandem, so that strength and durability increase along with size instead of degrading under the added weight. In its current state, the Quirk manifests in two fixed sizes: her base height of 162 cm and her maximum height of 2062 cm, with no intermediate dimensions. The transformation is reversible and leaves no structural damage to the tissues. The true limit does not lie in the biology of the Quirk, which has no ceiling in terms of versatility, but in the total absence of conscious control over the properties of her own growth.

CURRENT LIMITATIONS:

Fixed Scale (All or Nothing): The Quirk only reaches two states, base or maximum, with no capacity to sustain intermediate sizes.

Unified Body: Growth applies to the whole body simultaneously. The user cannot enlarge isolated limbs, which prevents her from concentrating the scale on a single point.

Mass Bound to Size: When she grows, mass increases proportionally and unavoidably. The resulting weight causes constant collateral damage and forces her to require open spaces to operate, rendering the Quirk impractical in enclosed or urban environments.

Involuntary Activation: Under intense emotion, Gigantification can trigger on its own, a sign that the user still lacks full control over its activation.

UNTAPPED POTENTIAL:

Variable Scale: Latent capacity to adopt and sustain any intermediate size in a stable manner, with a scale ceiling and floor that only widen through training. A single maximum size ceases to exist.

Localized Gigantification: Independently enlarging specific parts of the body while keeping the rest at normal size. Allows her to concentrate the full power of a giant's blow without exposing herself as a full body target, and to operate in confined spaces.

Density Control (Independent Mass): The true evolution. Decoupling mass from size and consciously choosing how much effective mass is concentrated during gigantification, with two opposing poles and a combined application:

- Titan Form: maximum size with weight reduced to a minimum. Gains enormous ease of movement and agility, capable of moving at high speed without shattering the ground beneath her feet.

- Colossus Form: concentrates a brutal amount of mass in the body, so that every step, blow, or landing releases a devastating impact.

- Combined Application: keeping the body in Titan Form to move light and nimble, and densifying only a specific part of the body at the instant of impact to finish with crushing force.

SUGGESTED EVOLUTION PATH:

- PHASE 1 (Scale): sustaining intermediate sizes to break the "all or nothing" habit.

- PHASE 2 (Localization): localized growth, starting with the fist.

- PHASE 3 (Density): mass decoupling, first lightening, then concentrating, then combining.

- PHASE 4 (Mastery): manipulation of body weight even at base size, without the need to gigantify.

- METABOLIC WARNING: brutal caloric cost. After an intense deployment, the user suffers extreme hunger and risk of collapse. Requires a hypercaloric diet and careful management of reserves.

CURRENT STATE UNDER BOOST EFFECT: The energy cost is reduced, and transitions of scale and density become faster and more stable, with a notably longer sustainable duration.

[ANALYSIS COMPLETE.]

"There it is," Izuku murmured, floored by everything it meant. "Gigantification... Miss Yu, you're... WOW. I just don't have words to describe it."

"Good for you," she panted, one hand covering her face. "C-can you get your hand out of there now?"

Izuku hadn't noticed. With all his attention on the lines of light floating in front of him, his fingers had kept climbing on their own, and only now did he register the different heat under his hand, much higher than where he'd started, at the exact point where Yu's thighs stopped being thighs. He lowered his gaze slowly.

Oh no. Looks like I'm getting sent back to the hospital.

"How long has my hand been...?"

"A good while." She was still covering her face, refusing to look at him. "I figured the big genius would eventually notice on his own."

Izuku yanked his hand away at top speed and raised it up high, far from any compromising area, palms toward her as proof of his innocence.

It's over, this is the end of my career. I touched a professional hero on... ah, I can't even say it. And the worst part is I didn't even notice. What kind of person gets distracted in the middle of THAT?

"I'm so, so sorry, Miss Yu, I really am, I didn't mean to, I mean, I did mean to, but, uh, no! Forget that last part! The point is my hand did it on its own while I was focused on the reading, and you're a professional, and this is unforgivable, and I've already been hit like three times this week, so if you're gonna hit me, at least give me a heads up so I can mentally prepare..."

"You done?" Yu slowly lowered her hands and looked at him sidelong. Her cheeks were still red, but a smile was starting to appear. "Because, kid... for someone who gets so nervous, your hand has quite a mind of its own."

"The good thing is you're a witness that the dirty one is my hand," Izuku shot back, pointing at the traitorous limb with his finger. "I'm a proper future hero, I hope this doesn't ruin the professional image you have of me!"

Yu rolled her eyes at the excuse. From outside the room, Nemuri's laughter could be heard, clearly delighted with the show.

"Oh, please, go on, go on. This is the best therapy I've had since I broke my leg. Don't hold back on my account; act like I'm not even here."

Yu decided to cut straight to the only thing she really cared about.

"Okay, enough. Cut the runaround and just tell me. What did you see?"

"What did I see?" Izuku straightened up, his entire posture shifting. "Miss Yu, your Gigantification is being wasted. And I don't say that as an insult, I say it as the best news you're gonna hear in years."

Yu arched an eyebrow.

"Hey, rookie... watch what you say about my Quirk."

"Don't misunderstand me." Izuku ran a hand through his hair, searching for a way to break all this information down without sounding like a textbook with legs. "Your Quirk has way more versatility than you're taking advantage of. Your body can adapt to enormous growth, but right now you're not fully controlling the properties of that growth."

Yu stayed quiet for a few seconds, crossed her arms as best she could with the sling, and smiled arrogantly.

"Oh, really?" She tilted her head slightly, clearly interested. "Are you telling me my Quirk still has a bunch of tricks up its sleeve?"

Izuku nodded.

"Exactly."

Yu's smile widened.

"Heh. Now we're talking about something interesting."

"What I mean is, right now your Quirk kinda works like a switch." Izuku raised a hand. "It goes from a normal person's height to twenty meters... and that's it. There doesn't seem to be anything in between those two extremes."

"And that's bad?"

"No! Well... not exactly." Izuku quickly shook his head. "What I'm saying is, there could be more options. A lot more. If you can control how much you grow, you could pick whatever size you need in the moment. Five meters, eight, ten... whatever."

Yu stared at him.

"Are you saying I could change size at will?"

"That's what I think." Izuku scratched the back of his neck. "It's just a theory for now, but it makes sense. Your body can already handle that absurd amount of growth. So... why would you have to be limited to being small or huge?"

Yu's arrogant smile faded little by little, replaced by a much more attentive expression.

"Wait... intermediate sizes?" She leaned slightly toward him. "Do you have any idea how many times I've had to hold back in an alley because I'm too big to fit? I'm either normal or a building with legs! There's no middle ground."

"Exactly! That's the problem." Izuku pointed enthusiastically. "And that's not the only thing. I think you could also control the growth by parts."

Yu blinked.

"By parts?"

"Yeah. An arm, for example. Or just a fist. The rest of your body would stay the same."

Yu's eyes went wide.

"Just an arm?!" She sat up quickly on the couch, completely forgetting about her ankle. "Then I could just be standing there, all chill, in front of a villain and..."

She raised her fist, her smile getting bigger and bigger.

"BAM! Giant punch!"

"Yeah." Izuku smiled. "And then you go back to normal before he can even react. You don't need to turn into a full giant to hit like one."

Yu stared at him for a second.

Then she burst out laughing.

"That'd be awesome!" Her eyes sparkled with excitement. "Kitakore! I can already see it in the news: 'Mt. Lady debuts her new giant punch and leaves a villain crying!'"

"Hahaha... well, that's not everything either." Izuku lowered his voice a bit, as if he'd just remembered something. "There's one more thing. Size and weight don't have to go hand in hand."

Yu furrowed her brow.

"Wait. What do you mean?"

"That you could grow without having to get so heavy." Izuku made a gesture with his hands. "Imagine you're huge but still light. You could move a lot faster and wouldn't have to leave the pavement wrecked every time you take a step."

Yu blinked, a little confused by the explanation.

"And that's where it gets interesting." Izuku smiled. "At the moment of impact, you could make all that weight concentrate in your fist."

Yu lowered her gaze to her own hand and stayed thoughtful for a few seconds.

"So... I could move like a giant..."

She slowly raised her fist.

"...and hit like a building fell on top of me."

Izuku let out a small laugh.

"Yeah. Pretty much."

Yu smiled.

"I like it."

"I knew you'd like it."

"That changes a whole lot of things." Yu leaned back on the couch, still looking at her hand. "Do you have any idea how many times I've had to think about where I'm gonna land so I don't crush a car? Being a giant's great until you have to think about every single step you take."

"But if I can control how much I weigh... I could move without having to worry so much about the damage I'm leaving behind."

"Exactly. And there's still one more thing."

Izuku raised a finger.

"You could also do it without growing."

Yu's smile dropped.

"What?"

"Controlling your weight while at your normal size."

Yu was stunned, unable to believe what was coming out of Izuku's mouth. It was something completely different from anything she'd ever thought she'd be capable of doing.

"...Even like that?"

A slow smile began to appear on Yu's face.

"So my Quirk isn't just about making me big..."

She looked at Izuku.

"I can control my size, how much I weigh, and how much I can concentrate that weight."

Izuku nodded.

"If you can master it, yeah."

Yu watched him for a few seconds. Then her smile turned much more competitive.

"You know what that means, kid?"

Izuku shrugged.

"That you're gonna be on the news even more?"

"That I haven't come anywhere close to my peak yet... The ranking better watch out, then."

---

A/N: Phew, this one took way longer than I expected, so sorry for the wait on the update. This time I really fried my brain putting together Mt. Lady's manual. I wanted something that lined up faithfully with her Quirk, so it took me longer than usual, deleting and rewriting the same manual over and over. On top of that I had to dig through the wiki, figure out exactly how it works, whether it has any limitations... yeah, I'm wiped out, but hey, it's three thousand words.