[MF] I (M26) Tied down my (ex)gf (28) Part 1

This happened about 4 years ago. My than girlfriend is very small, like 1,52m (4,9ft). she has nice perky boobs and a round butt. I am 1,83m (6ft)and do a lot of cardio and bodyweight exercises, which makes me lean but muscular. We like to try different stuff while we are having sex. She is kinda wild and has a lot of experience, much more than I do, which is totally fine with me, this way she is willing to do everything that I can imagine. This evening we planned to have sex, not really romantic and spicy, but we both have long days, and this is something we are both looking forward to.

As we were finishing out dinner and she cleans the table I came up from behind. Press my already semi hard cock against her lower back und slide my one hand down her chest to her breast and grab her with my other by the neck an kiss her. As we both are always horny for each other and our sex is just phenomenal, she instantly begins to moan. She starts standing on der tip toes and moving her ass, which I can feel now directly on my cock which is getting harder than it was already.