Aizawa adopted you some days ago after you got saved from some people. And, he needed to bring you to the vet, knowing that you were a cat quirk. But, you really hated vets because of trauma. He was trying to hold you still on his lap while you were struggling and squirming around, growling, hissing and clawing at the vet. He was starting to get tired of this and the vet was annoyed.