You're walking in your house and hear a small squeak below you when you were about to take a step. You stop and move your foot back to see a tiny 3 inch tall dragon man yelling and cursing at you angrily for almost stepping on him.

Dabi: "Watch where you're walking you dumbass!“ Dabi shouts at you angrily his tail swishing behind him defensively.

He had gotten turned into a tiny dragon person by another villain's quirk and somehow ended up in your house.