[M4F] My girlfriend gives full consent for me to fuck/breed her best friend or cousin... Obsessed with talking about/playing cheating on my girlfriend with her consent!

Everyone involved should be 18+

First idea. After years of bad experiences with men she's sworn them off completely. She is beautiful but has been treated very poorly so she is very insecure and borderline shy. She has known me a long time through my girlfriend and trusts me. She finally feels ready to get back out there and asks my girlfriend straight up if she can have me for a night to get her confidence back and remember what good sex feels like. We can do the slow gentle romantic route where I take her out on a date and reassure her all the way, or we could do a scenario where she wants to try out all the kinky things she's never had the trust to try with another partner. Cheating or open with permission both work.

Second idea. My wife or girlfriend is infertile and really wants to be a mom.  One of her close friends or cousins volunteers to get bred by me so we can start a family. My wife knows and gives full permission. This one can be caring and emotional or straight up breeding kink focused with lots of dirty talk about filling her up and getting her pregnant. Again we can mix romantic and kinky and do it over multiple nights.

Both setups have that theme of me being with another woman with my wife's blessing though sneaking around can be added if you like that. Refs are open to whoever you want to play, but I have some favorites posted on my profile and on this post.

I am 27 experienced with RP and I like building tension and real emotions and also straight up smut. Tell me in your first reply which idea you want and which direction to take it plus any hard limits or specific kinks.