[SHHH DON'T REMIND HIM HOW LITTLE SEX HE'S HAD LATELY. IT'S A DEPRESSING THING.]

How do you tell?

[You're asking a guy that assumes everyone hates him until they spell otherwise out to him, OKAY. But okay, he can fake it, right? Just think about...other people!]

Well...it depends! Everyone will react differently. I mean some might out right tell you, others...well-

Do they like spending a lot of time with you, or get easily flustered with you when they don't with others?