This is a verb that also has a noun version - fleaver.
A fleaver is that annoying person that frequently sits near you, talks about something with you, farts (without you knowing) and leaves.
A fleaver will most likely deny responsibility for the fart if accused.
(Three friends are talking and one of them says that he must leave or his wife will kill him. However, little do the other two know, that third friend has just farted.)
One of first two friends: oh. oh man that's rank. I think jim just fleaved!!
To flirt with someone and never ask about them later. Usually done without intending to ask them out or just a hook up hence the name fleave, to flirt then leave.
Person#1: man Jessica is like my girlfriend what are you talking about?
Person#2: im telling you, she was just a fleave man!
Flips weave. To flip one's weave as an act of negligence.
Guy: Hi, I heard that you wanted to go out this Friday, so I was wondering if you wanted to see a-
Girl: FLEAVE. *Flips weave*