The idea I have is:
Slave trading post, newly captured slaves that haven't been through whatever kind of training the traders offer are sold for dirt cheap. A young woman walks in and buys a slightly older male (30 at most). General appearance idea, blond hair and muscular. Not huge, just in shape. Once she buys him and has him back at her house in her room, she switches the roles. She lets him have power. How he uses it is up to the other player.
There really isn't a specific time period. I was thinking modern.
Please do read my ons/offs first though. There should be a link in my signature.
Not necessarily needing male players, I just need someone willing to play the male character.