A girlfriend (or boyfriend) who won't leave you alone. He or she constantly has to know what, when, how, and with who you are doing anything and everything. He or she constantly calls you and wants you in his/her sights 24 hours of every day. This term could also apply to an obsessive admirer.
See the terms Charlene
for further reference.
Ryan: Hey Dan, what are you doing tonight? Wanna play some COD 4?
Dan: No, I cant. Erica is coming over tonight.
Ryan: Wasn't she over every night this week?
Ryan: Jesus christ, she's a fuckin stage 5 cling-on.