I don't have much experience so as of now most things are only fantasies. Here is one.

I have a collar and leash on and you lead me on my knees to our play area. There you grab an inflatable butt plug and work it inside me. My cock is bound and my balls are being stretched by the collar weights you have attached to them. You sit on your throne in front of me and open your legs and demand me to start worshiping. As I lick, you continue to pump air into and release it out of the butt plug so my ass gets very stretched out and ready for what is coming next.

After you orgasm into my mouth you lead me to a bondage horse and tie my hands on one side. You attach a spreader bar to my legs to open them up and so I really can't move you take the weighted collar that is around my balls and chain it to the spreader bar. Now I am in the perfect position for you to have your way with me.

You are behind me now and I don't know what is going on. You put on your favorite strap-on. It is a huge black cock that measures 12 inches long by 3 inches wide. You start teasing me and verbally humiliating me about how you own my ass. How I might be a macho man in the real world but I'm really just your property to do with as you please. You take out the butt plug and start lubing up my ass cause you know I have never been stretched this far before. You slowly start inserting your cock and I clench my teeth and groan. I try to move forward but my balls are attached to the spreader bar so I can't. You tell me to relax and give you my ass because you own it, and one way or the other you are taking it. I try to relax and it slides in deeper. 

You start fucking me, slow at first then faster and deeper till I am taking the full length inside me. What a wonderful feeling to be completely helpless and in your control. You have taken me further today then I have ever been and you are pleased with me. You de-mount me and come around to the front and make me suck on the strap-on that just moments ago was all the way inside me. 

You untie my hands and feet and lead me off the bondage horse and to our toilet. this was a difficult trip because you left the spreader bar on with my balls still chained to it. I lie down with my face under the seat and you explain that you have a special treat for me. You leave for a moment and when you get back you lift the spreader bar up which raises my ass into the air. You place a funnel in my recently fucked ass and you remind me that you own my ass so using it as your toilet is your right. You let your warm golden nectar fill my ass cavity and it is an overwhelming feeling of joy. When you are satisfied that my hole is filled up you take your position on the toilet seat and reward me with the rest of your heavenly pee into my mouth. I swallow as quickly as possible so that I don't waste any. When you are finished I lick you clean. 

You take the funnel out of my ass and the spreader bar off my legs. You leave the ball collar on because you are trying to stretch out my tight balls for further use. You order me to shower and when finished I bath you and cook dinner for us.

Hope you like this scenario.