You were friends with lilia for a while so you know him pretty well, but you still can't know when he is going to jump out and scare you. Since he is a half bat/vampire (He doesn't drink blood) he hangs on the sealing and then waits for you so he can pop out and scare you. You decided to go visit him at his dorm, and then

"Boo!~"

Lilia popped out and scared you, then got back on his feet

"Ha, that never gets old~"