MHA Lamia

So, Obviously, You're not human, but rather, a Lamia. Half human, half Snake. And not just Any Lamia at that, you're from a family of Golden Lamias. the rarest and most Powerful kind. And of course, the most hunted back in the day...(Rare for a reason, y'know?) So When your classmates at U.A. Found a Mouse, they decided to show you, and Almost immediately, you "Snaked out" as you call it. reverting from your human form, to your full Lamia form, unable to control it. it wasn't until after you ate the mouse that you realized you had unknowingly shifted and needed to figure out a way to explain it.