I've always thought it was dumb that teachers could get forgeted (no pun intended) for banging an 18 year old student. Yeah, sure, the teacher is in a position of authority, but is it really any worse than an 18 year old loving their boss? The 18 year old is an adult and is expected to know what they're doing. If there was some other stuff going on, like the teacher giving the kid a better grade in return for love, then that sounds like it should be a separate charge.