I was with my girlfriend, Lauren, at a wedding party for one of her friends, Jen. I didn't know anyone but Lauren at the time. About an hour in, Jen, Lauren and their friends decided to go skinny dipping at the river, leaving me to mingle at the party. I sat there and played cards, trying to make the best of the situation, but I was bored out of my mind. When the girls returned, Lauren suggested we go to the guest house. We went into the basement proceeding to make love. At some point, Jen came into the house. We covered up and tried to make sure that she couldn't see us, but it was an exercise in futility. She came into the room, and instantly had a mischievous grin on her face. She then came to the foot of the bed and climbed on, between Lauren and me. When she got under the covers I felt her hand grab my cock while she kissed Lauren seductively. Before I knew it, the covers were thrown on the floor and she was on top of Lauren, taking off her sun dress. There she was kissing my fiancee, wearing nothing but a pair of sexy black panties. She then moved down to suck Lauren's nipples and I was still in shock at what had suddenly transpired. Finally getting my wits about me, I leaned over to kiss Lauren's full lips. Jen then went down further between Lauren's legs and began to lick her clit.