I used to openly fuck my stepsister.

So, title. She was my first sexual experience growing up, and my dad and her mom encouraged us to explore with each other. Nudity was common and preferred in their house, and mom taught the kids how to french kiss. We used to share a room and often a bed, and we would skinny dip in their above ground pool when everyone went to sleep. My step sister is also bi, and we got to play with one of her best friends together. Had experiences with her and her mom both. Definitely willing to talk about this more in private.