The usual caveats apply here.
In addition I had help early on from a Literotica member who shall remain nameless because I lost her address and have not her permission to name her.
Also as usual---No oversize equipment and no ANAL or other cruelty acts here.
Finally some of the more eager beaver guys will find the story too slow and short on the detail they love.
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My name is Don I was 20. My sister Donna was 19 and her roommate Gloria was also 19 when these events took place.
When Donna went off to college she was assigned a roommate whose name was Gloria. As Gloria needed to pass through our town to get home Donna would sometimes hitch a ride home from Gloria.
Once when Donna rode home with Gloria the weather was bad and Gloria spent the night at our house. That was how we met. Gloria and I got on great and before long she and I were going steady.
Donna had a boyfriend, Jimmy, and the four of us double dated often when we were all home.
During the Summer Gloria and I gradually progressed to having sex.
By the end of summer she and I were engaging in both oral sex and in intercourse to the great enjoyment of both of us.
Meanwhile my sister Donna and Jimmy were on much that same path.
As a finale to the summer we four spent a long weekend at a lakeside cabin belonging to Gloria's uncle.
There was only one bedroom and a queen size hide-a-bed. We all knew of course what the other couple was doing so their was no pretense.
Naturally we all spent a great deal of time in our respective beds but we did also have a good time on the lake and we did visit some local eateries.
Obviously I saw my sister in very erotic circumstances since we often walked around in the nude and nobody complained if someone walked in on the other couple without knocking.
A couple of times we saw each other in the throes of passion so to speak meaning in the midst of intercourse or oral sex.
Under the circumstances I occasionally developed a hardon when seeing my sister and having a visual of her in a sex situation. Anyone who noticed took it for granted that it was Gloria on my mind.
We didn't swap of course since Donna was my sister but that didn't stop me from an occasional fantasy illusion.
Back at college I had found a room to myself and I studied hard and get good grades. But when I wasn't studying it wasn't unusual for me to be masturbating.
When I did my fantasies covered a range of people. With increasing frequency the subject of my fantasy was my sister Donna.
Another frequent fantasy was of witnessing an encounter between Gloria and Donna. I had heard so many stories about college girls doing it with their roommates that it was easy for me to imagine Donna and Gloria together.
Sometimes my masturbation visual was so compelling that I would come all over myself almost instantly.
As always when we were at home Donna and I spent a lot of time together. Mostly it was late evenings, either in her room or mine. Most often we were dressed for bed.
Although I frequently got a hardon, I managed to keep my desire to myself. She was after all my sister.
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Donna-continues the story.
Yes. Darn it. He did keep it covered and he was so subtle about it that for a long time I wasn't aware. The aforementioned wild weekend was in a sense my coming (no pun intended) out party. No pun intended.
Up until then, while I was certainly no virgin and I had enjoyed numerous sexual encounters, it was all just for the fun. It was not wild, hot, can't wait, passion. That weekend though I somehow became a 'horny broad'.
After we returned to school for the fall semester Gloria and I began to talk about what it would be like to have sex with other girls. In our dorm a number of the other girls were bi, and some of them were quite open about it.
It was often called LTIG. (Lesbian Till I Graduate). Actually it was mostly BTIG since most did date guys. The saying was that being bi just doubled you chance for getting laid on Saturday Night.
That piqued our curiosity, but we didn't act on it, I think because of a mutual fear of losing the other's friendship. Talking about it was exciting and led to some great Joint late night masturbation but that's as far as we went.
One early spring weekend the four of us had planned to visit a nearby natural wonder. We were to share a motel room overlooking the canyon and falls.
Don suddenly had to cancel in order to go home and aid our dad in some business project.
Gloria, Jimmy and I went on without him. Before the weekend ended we had ended up in a wild threesome. It was totally enjoyable and none of us felt threatened by the event.
Both Gloria and I admitted that it was exciting watching each other having sex with Jimmy.
One thing that we realized as we rehashed the weekend later was that we unwittingly each tasted the other's pussy.
That being when we'd sucked Jimmy's cock after he'd fucked the other. We both acknowledged that we enjoyed the memory.