[MFM] My girlfriend ended up on her knees in front of me and my friend

Me and gf have been together for 4 years now and everything’s going great except the fact that the sex is starting to become a little bit same same. But that’s probably the case with most couples that’ve been together for a longer period of time.

Anyway, my gf is a cute, red haired 25 y/o, and I’m three years younger. Her body is pretty normal in terms of height and weight but her chest is super big and heavy (like double D’s), and easily the hottest thing about her. I’ve always loved them.

We started joking about introducing a third part in the bed since both of us are bisexual, but we’ve never come further than that. Until last weekend.

My buddy threw a party that we attended and my gf went over there in a black dress showing a VERY generous amount of cleveage. I could notice some of my friends starting at her chest from time to time during the whole evening. It turned me on so much!