I'm getting the same issue too, and it's always when I interact with a girl a second time. I try to exit the scene, and the frame rate drops to about 3 fps and I have to force exit the game. I start the game up again and begin, and the game tells me that the girl I was with is now "broken" and if I try to interact with her again, the same thing happens. The only way I've found to undo this is to completely delete the girl and re-create her. This has only happened with custom girls, that I've noticed. In my opinion, this is a game-breaking bug and makes the game kinda unplayable for me.