My best friend's birthday

My name is Pete and I have a very good friend. Her name is Jane and we know each other for many years. Best friends in the world. We share the same humor, we like the same movies and we can talk about everything. And while she is a beautiful woman, we only had this platonic friendship without any romantic feelings or sexual desire... OK, there were some moments, where I thought about the possibility, but I loved our relationship and didn't want to lose what we had. So we only were good friends. Until this day in June.
It was her birthday, and I had been invited to dinner with her and her boyfriend. His name was Rick and he was a nice guy. But as I arrived, he wasn’t there yet. Jane wanted to talk to me alone. She was a little bit nervous, but then told me, what she wanted from me. Rick agreed to a fantasy of hers (as a birthday present). Another man should watch while they have sex together. And Jane wanted me to be this silent man in the corner of her bedroom. Now I was nervous, but I agreed as well. I mean, she was my best friend and it was her birthday wish.
So I walked into her bedroom and took place at a sofa, where I had a good overview of the room. After some time I heard the arrival of Rick and some minutes later both of them came in. They started slowly taking off the clothes of the other. They started kissing and touching. They had sex in different positions. And during most of the time Jane looked me in my eyes. This eye contact drove me crazy. I was horny and wanted to put out my dick. I was shy, and didn’t do it. Until Jane read my mind and gave me her ok with a blink of her eyes and a little smile, that put my heart into flames. So I took out my cock and started wanking. Jane looked me in my eyes while we both came to an orgasm at the same time. Rick came shortly after us by the hands of Jane.
An hour later as we sat down for dinner, Jane asked me about my thoughts. I told her, that I would have loved her hands on my penis at the end of the game. She smiled and said:” Who knows? Next month is your birthday?"