Tweeping is when an adult male or female aged 25 years or older likes to hang out with tweens or teens of the opposite sex, for long periods of time, and usually late at night. This is especially creepy, since most adults at that age like to hang out and party with actual adults. Another sense of the word would be tweeper, or tweeps.
A neologism between the words tripping and creeping. So pretty much a person who secretly knows information about you by creeping on you, and is tripping because they think you don't know.
"Dude that girl who's ex is dating my ex, wants me to go the club with her.", "Oh she treepin' on you then!