ALB-200 - My Best Friend's Little Sister, Miyu: Getting Down and Dirty in My Dorm

The scene where they suddenly hide and have sex in a closet. The thrill and the confined space make it so erotic. There's also a scene later where they do it next to someone sleeping, but I found the closet scene much more exciting. She might not be drop-dead gorgeous, but there's something about the way she gets aggressively pushed that just works.