I had a couple of ideas I'd like to do...
A boy's parents go on holiday and leave him with his older, grown sister. She has secretly resented him from when they were younger because he was their parents favourite and she decides to get her own back and show him who's boss. Lots of kinks we could put into that one, so if you like it then we can work those out.
A wealthy business man buys himself a sex slave - not too hard to work out what's going on in this one! As a twist, she could find something to blackmail him with whilst cleaning his house and uses it to elevate herself to a position of power and get him back for the way he treated her.
PM me if you're interested and we'll work out the details. Strongly prefer to RP via Instant messenger, YIM, AIM, all that stuff.