Well, darn. This is hard to rate. I loved the prompt, loved the characters, loved the writing....
A Pirate and a Genie, sex toys, spanking and paddles. I mean, who doesn't love a pirate and a spanking... I mean a submissive redhead?
On the other hand, we never get to see the world in which our heroes live, being stuck in the Captain's cabin and his bed.
Jumping from scene to scene is often confusing, I wasn't always sure where I was, where the characters were and what was happening.
Sex, sex, sex... and more sex with sex on top. Not my thing. More sex O.o
And, of course, masters: the former master, a previous master, all other masters, the current master aka just "master" and then, of course The Master aka "the current master", but on a whole new level.
So... I am thinking 3 stars? Sounds about right.