One for All, a Quirk made to pass down power from successor to successor. It has accumulated power and Quirks from eight people over the years, and now rests in the ninth, Izuku Midoriya.
Izuku, who was born Quirkless, is a student at the prestigious U.A. School, where those who aspire to become Pro Heroes go. His classmates have come to believe that his Quirk was a strength enhancing ability. However, within One for All are the Quirks of previous users, which had merged with it and were also passed down. And today, one such Quirk would rear it's head.
In the middle of class.
[A transformation type Quirk that allows the user to become a werewolf. Stay away from silver and full moons.]
Everything in class had stopped in an instant as everyone stared at Izuku. The boy was so engrossed with his schoolwork that he had not noticed that a pair of wolf ears had sprouted on top of his head or the glossy tail that popped out the seat of his pants, though the others had noticed instantly. Iida was the first to question him.
"Excuse me, Midoriya?"
"Hmm? Is something wrong?"
"Have you noticed something... out of the ordinary?"
"Something out of...? Well, I did think that I noticed something different between Kamui and Mt. Lady during their latest appearance. They seemed to be a bit closer-"
"Not that! I mean-"
"Would you please put your hands on top of your head, Midoriya?" Tokoyami interrupted.
Confused, Izuku did as he was asked. "Uh, alright, but I don't see why..." He trailed off as he felt something under his hands twitch. "Wha?"
Tooru handed a hand mirror to Iida. "Here, it might be easier to show him."
"Wait, why does an invisible person have a mirror?"
Izuku looked into the mirror that Iida pointed at him. "Huh?"
"WAAAHHHH! WHY DO I HAVE EARS ON TOP OF MY HEAD?!"
"How did it take you this long to notice?!"
A new sensation on a body part he never had before snapped Izuku's attention behind him, where Ochako was feeling his new tail.
"Oh wow, it's so fluffy!"
"I got a tail, too?!"
"Oh man, Midoriya turned into a furry!"
"Hey scoot over! I wanna pet his tail, too."
"Wait, sit down, all of you! We need to figure out what is going here!"
Everyone looked toward Izuku as he looked about to sneeze.
"Yo, are you allergic to yourself now? That's gotta suck."
After he sneezed, Izuku noticed everyone staring at him now for an entirely new reason.
"Does this still count as furry?"
Confused, he looked down to see what was wrong. His body was now that of a large werewolf stuffed into a school uniform. He was covered in dark fur, though he still had a mop of messy green hair. He also rivaled Mezou in size, now.
"Someone go find the teacher!"
"What's that, boy? Tiny Timmy is stuck down the well?"
"Izuku, hold still I need to pet you now."
"Uraraka? Wait, Yaoyorozu?!"
"I can't help it, he looks so fluffy!"
"Catch him, he's going Full Cowl to escape!"
Aizawa stood in the doorway to the classroom watching the events happening inside before turning around and leaving.