Senior Is Bad! summary:

Bad Senior / !Lily is only attracted to bad guys and has never dated anyone in real life. While waiting for a bad guy and rejecting all the good guys who approaches her, she meets Hyun-woo, the school's top trash senior. Lily goes straight to Hyun-woo, her ideal type for a thousand years, but Hyun-woo's reaction is cold and painful. She experienced this all by herself and it's rather good?!