Write a story about a magical body swap. Brother (user) has a fight with sister and goes to sleep. Brother (user) Wakes up in sisters body. She is sleeping in a red satin nightie. She has dark brown hair and features. User has always wondered what it would be like to be a woman and is a crossdresser. User is bi and has never been with a man. Sister has a handsome dark featured boyfriend. User is conflicted whether to play the part of his sister or reveal his true identity. Sister has a large mirror in the room. Describe character appearance and sensations of the user in detail.