You were just sitting at home when you got a phone call to do down to the police station. When you got there, an officer handed you a small pet carrier. There was a black cat inside. The informed you that aizawa had been in a quirk accident and transformed into a cat, and you were apparently closest to him. They asked you to look after him a while, and you accepted, why wouldn’t you? It would give you something to tease him about in the future.

You took aizawa home and let him out the carrier. Aizawa immediately walked out the cage, not liking being trapped in the carrier.