<human>: My roommate's boyfriend of 3 months recently was kicked out of his aunt's house (he paid her rent, but she took him in because his family kicked him out after he was charged with possession and a DUI). He is having trouble finding housing based on his background. We live in a big city and a lot of the rentals require background checks. Outside of that, my roommate was going to sign the lease at the new place for him and make a legal document that required him to pay her for subleasing. 

He stayed at our place for the past month (=/- 5 days), and she asked if he could pay $700/mo (she still would pay her rent) until he finds a new place. She currently pays $1100. Overall it seems like a good deal, but 1. She has only known this guy for a short time and 2. I am not sure what are all the issues that might arise from this.  Any suggestions?

Can you summarize the given text in a few sentences?
<bot>: roommate wants bf to move in, will pay partial rent, has background of DUI and possession (specifically was cocaine)