I would greatly enjoy doing an Rp where you are perhaps a Female/Hermaphrodite/Futanari Dominant and I might play a submissive Feminine male. As for plot there are numberless ideas I could list and expound on. I'm not really sure what would fit you best but I'll put a few basic ones down for now. Please feel free to change and amend them to your liking in a reply Pm.
A gender reversed beauty and the beast. The beast being a once spoiled princess now turned big feral monster.(could be furry, more monster ish, dragon perhaps, werewolf, etc) Then my character might be the a sacrifice from the local collage spurned for his Submissive nature and given up more to be rid of him then sate you. From that similar to the story a D/s romance blooms from the feral rape and conquering of the boy to your liking. (perhaps Futa?)
A Female/Futa pirate captain takes a young nobleman captive and holds him for ransom but ransom but receives no payment. Thus infuriated you rape and claim him as nothing more then a slave to work on your ship. To teach those nobles a lesson you make him pay by becoming the lowest of the low degraded and used by you and you're crew as well as being forced to work. Then after a long period of abuse to where it becomes the norm and he is long since broken you see him for how beautiful he is so delicate and kind and submissive. When you ask he obeys when you look unhappy he always asks how he can please you. You realize he has always loved you and when you ask him he replies "yes I do"
A mythical dragon in the high mountain overlooks a small village. You have usurped it for years eating it's meat and taking it's gold. You have even seduced men from it multiple times in all three of your forms human, anthro, and full feral. But now you wish to seek new stomping grounds and you don't wish to leave alone. There has been a male there your have watched grow up. You have seen him grow from boy to man and his delicate features and beautiful face and body has always attracted your eye. So you decide to take the young man with you to be your mate/pet/I don't know. There are lots and lots of D/s fun to be had here with the feral and anthro forms and perhaps with you being so magical your sexual fluids are too and can keep him alive indefinitely with regular doses among other effects.
Just some ideas off the top of my head. Enjoy!
Please Pm!! I will try to amend and add more stories as they Come to mind.