A younger/teenage girl who deliberately comes between a guy she likes & his girlfriend, by pretending to just be a friend then getting him to spend all his time with her, till the girlfriend dumps him. Leaving it clear for her to make a move. - "Pulling a jessy."
Kelly - "What's going on with you & James?"
Melanie - "He's seeing someone right now, but I'm going to pull a jessy."
Jake - "Did you hear about Steve dumping his girlfriend?"
Dan - "Apparently he's seeing some Jessy instead now."