When you need to pee really bad, it's generally good if it doesn't take that long saying it.
Mike: NTP. Brb
*minute goes by*
Mike: Bib. Party was great!
A straight male friend who will not try to sleep with a female friend.
He is like a brother, exhibiting completely non-sexual behaviour. He's not necessarily a "nice guy", but just a great friend that has nothing to do with sex.
NTP is the male version of the "fag hag", except both parties are straight.