Simp

Simp originally meant a man doing almost anything to get a little bit of attention from a woman.

But weebs adopted this term and use it as liking a fictional character or being in love with a fictional character.
Some people just use it as finding a fictional character attractive.

1. "You're a simp for insert female twitch streamer here}."

2."Bro I'm such a simp for Gundham Tanaka,,"