adj. Condensed "all up ons", ascribed to a person who is shamelessly flirting with someone else, especially when the flirter is blatantly disregarding flirtee's need for personal space; being all up in the grill of the flirtee.
speaker 1: Did you see Brandon last night? He was allupons my shit!
spearker 2: Dude, I know. It must have been that hot shirt you were wearing.