They're actually called Lacey and Nolan. And she was attracted to him because she was just on ecstasy. This is explained in the end:
Bob: I'm not the devil.
Nolan: Wait, this is amazing. I didn't sell my soul, which means Lacey really loves me.
Lacey: Hey, sorry I'm late. I just slept for 18 hours. I bet my friend that I could do ecstasy five days in a row and it wouldn't affect my life and I totally won the bet.
Nolan: Ecstasy? You said you were in love with me. You said my ass was adorable.
Lacey: Wow, I did? Well, that didn't affect my life, so I still won the 50 bucks. Yay me.