As true to her word, the next morning Ms. Yukizome visited the dorms to wake up her students to attend homeroom. For the next 2 weeks, all of the students of the 77th class attended class and each one went off without a hitch.

Until Nekomaru and Akane wanted to practice combat.

That day, Isaac walked into the class to see that there was a substitute teacher. She informed them that Ms. Yukizome had some other work to do in the school and told them that she was just watching them and they could do what they normally did. That was her first mistake.

10 minutes later the substitute was on the ground with Sonia and Mikan tending to her while Akane and Nekomaru having a full-on brawl. The entire left wall was utterly destroyed with the impact of the two duking it out. Isaac was sitting crossed-legged reading one of his favorite romance novels between Gundham, who was leaning against the wall, and Fuyuhiko who was also sitting down. The fight was pretty much one-sided with Nekomaru having the upper hand with his raw strength. Soon Akane was launched towards the wall as Ms. Yukizome walked in.

"Get up weakling!" Nekomaru taunted.

Akane wiped some blood dripping down her mouth as she got back up, "Oh I ain't done yet!"

Ms. Yukizome turned to the students on the wall and asks, "Anyone care to tell me what happened to the wall?"

Isaac replied without taking his eyes off his book, "Those two been going at it for the past 30 minutes."

"As amusing as this is, I guess we have to stop 'em," Fuyuhiko says with a deadpanned look on his face.

"Our substitute fainted dead away. The excitement was too much for her." Sonia says while sitting with Mikan, who's tending said substitute.

Ms. Yukizome marches up to Nekomaru, "That's enough! Listen up Nidai, you can't just destroy the classroom because you feel like roughhousing!"

Nekomaru sends a glare to their teacher as he bellows, "What did you call it?! I'll have you know we're training in real-life combat conditions!"

Ms. Yukizome blinks once as she walks away, "Oh, in that case, knock yourself out."

"So much for that." The yakuza says with the same deadpanned look.

"I guess if it's educational, it gets her approval." The bounty hunter replies.

"And so, the world fell, room by room." The breeder contemplated.

After getting a major boost from Teruteru, Akane's strength grew enough for her to be able to fight toe-to-toe with Nekomaru. Chiaki and Ryota left the room as soon as their punches had enough force to crack the windows of the room. Peko tried to intervene to stop them, but Fuyuhiko talked her out of it.

"Hey, Takashi?"

Isaac looked up from his book to see Mahiru crouching in front of him. "Can I help you, Koizumi-san?" The photographer glances back at the fight and looks back at Isaac, "Could you please do something about them? You're probably the only one who can match those two and I'm gonna have to meet up with a friend of mine." Isaac closes his book with a sigh, "Fine." He gets up, leaving his book on the ground, and begins walking towards the brawling teens.

"All right you too you had your fun, but it's time you-" Isaac didn't get to finish his sentence before the two teens both clocked him in the face. Hard.

"OH SHUT UP!" they both scream simultaneously.

Isaac falls to the ground and silence fills the room.

"Oh no..." Fuyuhiko says, sweat dripping from his face.

Kazuichi looks at him in confusion and Gundham remarks, "Hm, it seems he couldn't handle those two beasts." Fuyuhiko shakes his head before pointing back at Isaac's downed form.

Isaac slowly begins to move as he performs a kip-up and lands on his feet. The first thing someone would notice about him is that his nose is pointed in an awkward direction as he looks up at Akane and Nekomaru with a demonic expression. He reaches for his nose and snaps it back in place with a sickening crack, his expression not wavering. He then swings his coat off and tosses it to Ibuki, who catches it, and rolls up his sleeves.

"You're dead."

Akane isn't shaken up by Isaac's demeanor and punches her palm, "Oh really? Well, I'd like to see you tr-" Before she could finish her statement Isaac was already behind her, his hand gripping the back of her head. Before anyone could react, he slammed Akane down to the classroom floor, cracking it severely. Akane made no movement other than some twitching as she laid there, a small pool of blood forming around her head. Isaac then turns his gaze to Nekomaru, who is backing up, fear plastered on his face.

"H-hey Isaac, we were just messing around!" Nekomaru tries to reason with Isaac as the hunter slowly stalks towards him. When he stops in front of the coach, who at this point is sweating bullets, he gives him a sweet smile. "I know, just next time be careful about who you hit, okay?" Isaac lightly pats Nekomaru on the shoulder, a smile still plastered on his face. He turns his back, hearing Nekomaru breathes a sigh of relief before whirling around and deliver a powerful roundhouse kick to Nekomaru's head, blasting him across the room and through the classroom wall.

Every person in the class looks at the beatdown with a mixture of fear, amazement, and more fear. Through the hole in the wall that Nekomaru was sent through, Ryota, Ms. Yukizome, and Chiaki poke their heads in seeing what happened in the class. Isaac then walked over to Ibuki, who is frozen in fear when he approached her. He takes his coat from her, giving her a quick thank you, and returns to his spot against the wall, sits down, and retrieves his book. He opens it again and began reading before looking up, seeing all the eyes of his classmates on him. He cocks his head, giving them a questioning look.

"What?"

That day, the 77th class learned one thing: Never piss off Isaac.