A term used for somebody that is just sexually
attracted to somebody. They just wnats to
have sex with them, not date them or
anything.
Guy 1: Look at that girl! She's hot, why dont you date her?
Guy
2:
Nah, I'm just up onto her.
Girl 1: Wow, that
guy stares at me! I wonder if he wants to date me?
Girl 2: I think he is just up onto you.