I need some ideas

A girl meets two guys and befriends them. Later she finds out they are serial killers. Name a good reason why she needs to go back to these two men's home. Be creative and it can be anything... for example...she left her I.D. or she had a  math test coming up and one of them is amazing at mathematics.

please be very detailed and write it out in story form.

Please be creative you guys...I know there's plenty of creative people on here :)