He thinks I am. He gets erections and is kind of handsy and snuggly in his sleep when he's with me and if he's asleep I think he would just do it unknowingly, if that makes sense. She's adult, btw. I just think it's a bit weird, especially as it wasn't a totally necessary sleeping arrangement. They are a close family. His sister gets mistaken for his girlfriend sometimes because they tickle and wrestle 