I'm bi and engaged, my fiance and I have an agreement he get to know the girl I'm interested in, I can do with her what I please as long as I let him know, no secrets. He would love to have a threesome but I'm not sure how I feel about it. I dated both my fiance and a girl through out high school and my relationships never suffered. I personally thing you should do what you have to do to make your self happy. Be honest with your bf. If he can't take you the way you are he may not the one for you.