We had a fairly big St. Patrick's Day party at my house in university. We lived in a "hybrid" neighborhood with half students and half family homes. There were around 350 people in our backyard and there was apparently a lot of noise. Cops ended up coming and shutting everything down but we had a smaller group of close friends stay behind so we could continue the party inside.
Everyone was pretty drunk but no one was really out of control. We had a pretty good ratio of girls to guys as a lot of my roommates invited friends up from home. Everyone starts pairing off and slowly make their way to the bedrooms to either hook up or pass out. One girl had arrived after the cops broke up the party and had not been drinking for nearly as long as us. Since all of her friends were paired off she decided to hop in bed with my roommate who was already sleeping.
After the brief siesta everyone makes their way back out to living room to continue the party. One room in particular is making a lot of noise. It was pretty obvious my the new girl was having some fun with my roommate - nothing new it seems like that bastard is always pulling a girl. Eventually they finish up and join us back at the party. Everything starts to wind down and everyone goes their separate ways. Full day/night of party and no one passed out- a pretty successful St Patrick's Day.
Fast forward to the next day ~11 am. We're mid clean up and get a knock on the door. I look out the window and there's a police cruiser. Immediate thought is that they're following up about the noise complaint on the previous day. Nope.
Apparently my roommate has been accused of rape and they want to bring him down to the station for questioning. After arguing at the door with the police officers for 45 minutes at how ridiculous the accusations were they decided not to take him in.
She found out that she would have to be medically examined for proof but continued the lie for a few more weeks. Her entire friend group supported her claims against my roommates. She only admitted the lie when my roommate threatened legal action against her. Her entire friend group ostracized her after they found out. Good riddance.
TLDR; Girl embarrassed about hooking up with roommate, decides to try to ruin his life by accusing of rape.