While in college I had a fuck buddy who id occasionally sleep in her dorm. Well one night we were laying in bed and she started to reach for my dick to initiate things but I wanted to do something different. I hadn’t watched her masturbate before so I wanted to see. I asked her to play with herself while I rub my dick wishing it was inside her. She slowly began to insert a finger and a slight moan. You could hear how wet her pussy was always from just one finger. I asked what she was thinking about and she told me her sister. I was shocked but intrigued so I asked her to explain. She was thinking about how sexy her sister looks and if they weren’t related she would’ve asked to eat her out. I then laid next to her and whispered things to help her cum. Had her thinking about where she’d want her and if she was there what she’d do. Her moans got louder and 1 finger turned to 3. I asked her to moan her sister name. She kept saying louder and louder until she squirt all over her sheets. I’d love watching her get really into it and cum. I could tell she was really enjoying it. Wish we could’ve added her sister!