Using My Slave Martina With My Boyfriend

A lesbian domination story.
Ever since I met my boyfriend Triss, I had less and less time to meet my girlfriends, but somehow I always remembered Martina's words when she once said that I could not "cover her in jizz". So I finally wrote her an email asking if she had time so I could "introduce" Triss to her. She was happy to hear from me and looked forward to it.
We walked some through the city and I chose our way to lead us past some sex shops, which had the desired effect on Martina. She stopped and stared at the windows, while I still held her hand. I noticed it getting damp and felt what she needed. "Let's go inside," I proposed. She said nothing, but followed me and her eyes lit up. Triss came along behind us.