friendly threesome

One of my best friends at the time, Nicki, was going out with another one of my friends, Don. We had all been friends for a while. In fact, I had had a crush on Don and we had been together before he started going out with Nicki. Frankly, I did not like them together, so when I found out that they were having sex, I was none too pleased!
Both Nicki and Don are born in September, and jokingly, Nicki said that she wanted a threesome for her 18th birthday. And she wanted me in it! Don mentioned this to me, also in a joke, but as we started discussing scenarios the idea grew on us and soon we were making plans. Nicki and I went to school together and we spent a couple lunch times talking about it. Don's parents were going out of town for the coming weekend. The date was set. The plans were made: I would go home with Nicki after school on Friday, and we would shower (not together) and then go by Don's house. It bothered me that the two of them did not seem to mind me in their sexual lives, even though they were together and because of the obvious conflict of interest, ie the past relationship with me and Don.
Friday came. The plans were still on. I went home with Nicki. I took a shower, excited and nervous about what we planned. I was naked in her room, when she barged in. I did not expect her, since one of the "rules" was that we would not do anything without Don. She complimented me on my body. She did not leave, however. She walked over to me and touched my breasts. I quivered with pleasure. Her hands were soft and small and as her hands explored my body, I came to enjoy them more than I had any guy's. This scared me a bit. We kissed softly and slowly, our tongues met and our kissing got deep and harder. We were interupted by the telephone - it was Don wanting to know what time we were coming over. While Nicki was on the phone, I quickly dressed. Immediately after, we left to go over by Don's house.
It was kind of awkward at first, and we sat around and watched porn. Then Don started rubbing my leg. I was surprised that he touch me before he touched his girlfriend, but I liked the attention and obviously making Nicki jealous. His hand moved further up my thigh and he started kissing me. Soon, he unbottoned my top and gently caressed my breasts, playing with my nipples. He stopped and moved over to Nicki and kissed her. She took off her clothes and reached for his cock. He pulled away from her and returned to me, and continued to remove my clothes. Then Nicki came over to me and kissed me. Don stopped to watch us, with a huge smile on his face. Nicki moved down lower and sucked my breasts. Out of the corner of my eye, I could see Don jerking off as he watched us. I was still feeling a bit awkward about the whole situation when Nicki put my hand on her breast and guided my mouth towards them. Don came back to us (well to me) and started fingering me, while Nicki sucked his dick. I decided to really get into this threesome and join Nicki sucking his cock and balls. He enjoyed this immensely and so did Nicki and I! Don soon came and Nicki drank his fluids. After this, we stopped and went back to watching the porn - naked. Then Nicki started rubbing my inner thigh and slipped her finger inside my pussy. It felt wonderful and i soon started fingering her too. Next thing I knew, she was licking my clit and fingering me. I moaned softly and enjoyed her soft tongue as it explored me. I returned the favour and tasted her pussy. Don got so excited that he begged to fuck one of us. Since I was sucking Nicki's cunt, Don entered my pussy hole and started riding me. Then he fucked Nicki.
The next week we went back to school like nothing happened!