How I fulfilled by GF’s fantasy by fucking her best friend. [MF]

So I touched on this story a while ago over at /r/sex. Thought this would be a better place to go into it more extensively. This is the story about how I (30M) accepted my GF’s (28F) challenge of fucking her best friend. (27F) This is longish.

Me and my GF (let’s call her June) have been dating for quite a long time now. She’s an averaged height brunette with a smaller body frame and chest size, but one great ass. We’ve been very open with each other about our wants and desires since the beginning, even when we initially felt uncomfortable doing so. It has only made us all the more stronger. I couldn’t ask for a better lady. We’ve done all kinds of things that we other wise would have never thought about doing. As a result, our sex lives have never been better and we can’t help but fuck like rabbits on a neat daily basis.