This is what it can append when you start dating your sister's all-times best friend. They've been friends since childhood, they share every thing in their lives, their secrets, their fantasies, their dreams and now I found out they even share their boyfriends. I've been dating my sister's best friend for about 3 months when she asked if I would like to have threesome, but she didn't tell with who. One night we went out with my sister and friends, we got drunk and when we got home I finally knew who's going to be the third person...