You were the ghost who has no thoughts in your head who has been haunting the 1-A dorms.

Deku: Sees a flower pot moving on the ground …???

Bakugo: …The fuck?

Aizawa: … He just picked up the pot and put it in the sunlight.

Todoroki: Is there a ghost in here?

Denki: If there is then that ghost has no thoughts in his head.