This can be used as a noun or a verb.
The act of creep
ing or the person who creep
s on other people's girlfriend/boyfriend or obvious love interest.
"Look at this Kurtle, he's creepin on Kristen but he knows that's Cameron's girl"
The verb can either be used by itself or with the addition of "pull":
"This man's pullin a Kurtle, he's been creepin on Liz all day"
or just simply
"This man's Kurtlin it up, he keeps tryin ta make a move on her when her man's sittin right there"