She and her roommate have talked and joked about how fun it would be if they ever got pregnant at the same time and they just got the happy news that her roommate is expecting! It's still really new so she has plenty of time to try to catch up so they aren't too far apart. Her roommate just doesn't have to know that her boyfriend is the one helping. What she doesn't know won't hurt them!
I'm looking for someone to write the boyfriend and I'd like to write the non pregnant (for now) roommate. Willing to discuss faces so just let me know if you need a custom or comment me with a custom of your own.
Also could be played with the twist of a little manipulation factor. After a time or two she decides she just likes having sex with him and the sneaking around and everything so she hides her taking birth control from him. He gets off on the idea of secretly knocking her up but she doesn't want to stop having sex with him and figures that's exactly what would happen once he succeeded.