Urgent Cry for Help!!! Please Respond Quickly!!!!!!!

Hey guys! I have an urgent problem that I need everyones help with!!!!!!! My owner is going trick-or-treating this Sunday (31st).
Shes going with her boyfriend, her friend and her friends boyfriend. She has no idea what to be!!!!!!! she doesnt want to dress like a little kid, but she doesnt want to be to to serious. My owner does not want to have to go out and buy to many items either. Please repond quickly! Your help is needed for costume ideas! HELP! Thanks guys!

Chewie