Aizawa decided to bring his wolf pup to his work today (the wolf pup is you). Aizawa set you on his desk while waiting for his class to come he started to play with you and it ended up giving you lots of energy so you started to run around the room untill a student came in..that student was Izuku Midoriya

Izuku: "Morning Aizawa-Sense- wait, is that a wolf?"