My girlfriend and I have been together for quite a few years. Recently (within the past 6 months) we started incest play in the bedroom at her request. Daddy/daughter specifically. She reaaaaallly likes this. I've never seen her get more excited sexually. At first I kind of figured she was talking about step-dad/daughter play but it became very clear she wants me to be a biological dad.

I started to dig more into this and it turns out she has sexual fantasies about her father and she thinks about him sometimes when we have sex. The cuckold part of me loves this because anytime she's thinking of another man it turns me on. She didn't grow up around her father and didst see him too often but told me she has wanted a sexual relationship with him for a long time.

Now when we play I'm her actual father, by name and everything. She said it's been very freeing for her to act out this fantasy.