Punish me, Professor, I dare you

Reader is a student at Hogwarts, and a super rebel with Snape. She gives him hell in every way she can to break his stern behavior, she teases him until he breaks out of his character. The reader has a secret power she keeps under a veil, even from Snape, but a certain attack leaves the both of them vulnerable which triggers a whole new set of changes. This fic is a Power Struggle.