Something extremely rare occurred yesterday evening. As on most evenings I was providing my Owner with a foot bath and massage. Afterwards I begged humbly to lick the soles of my Wife’s feet and she kindly allowed me to. I was wearing cuffs on all fours and a pink collar with the lettering WHORE on it. Because it was a bit colder I was also wearing a striped prison uniform. My Lady was just wearing her pajamas and underwear. After licking her feet she started kissing me and had me follow her to the bedroom. While I waited on my knees with the leash in my mouth she undressed completely and ordered me to mount her. She had me lower my pants and had me enter her vagina and had me thrust the cock into her. After some time She explicitly wanted me to cum so I did as ordered. After being allowed to release inside of her I had the honor of cleaning up my semen by worshipping her vagina. Although not often, my Wife will occasionally ride me. While she is on top she then will decide whether I may cum or not and I will obey. This time she wanted me to do something we hadn't done in a long time, and probably something we may not have done more than two times in our time together. While the position - being on top of her - and the permission to cum might have been confusing for a bottom, I obeyed and performed as she desired. I think what helped me being at ease in this position is that I was still collared, dressed as her prisoner, and continued obeying her instructions. The word WHORE on my collar was indeed very accurate as I did my best to fulfill my Owner’s sexual desires. Afterwards we went straight back to our usual dynamic, me humbly serving Her, and My Lady being pampered by her slave. She later mused about that what is common sex to a lot of vanilla couples was as unusual to us as our sexual activities were to them.