Hola. Every now and then, I get the urge to do some solo D&D stuff with a layer of sexiness on it. I'm most familiar with 3.5, but can handle 3.0 and Pathfinder (to a given extent - there are probably plenty of little changes I don't know about). My preference would be 3.5 using material from the Gaming Den community, but that's not a requirement.
Anyway, here are the two ideas I have. Both have very different workloads for
Mister Cavern the other player.
1. Dungeon Keeper
Hats-off to Jeremiah for this one. I would play a villainess who has inherited or recently claimed a castle, underground dungeon complex or similar. Over time, I have to recruit monsters (through bribery, seduction, showing them that it's simply a good place to live, or outright coercion), work on Diabolical Projects (TM) and get the place kitted up to be a real evil lair. Every now and then, you can send groups of heroines to try to slay me, and then if I beat them... interesting things can happen.
This almost puts me in the role of being the Dungeon Master, except usually the DM plays to lose and holds all of the "other" facts of the world. In this case, I'd be working on the dungeon and controlling monsters and such, but it'd be up to you to determine what is actually in a given place I search, and you'd be the one to decide when heroes strike, and who they are, and they'll probably lose eventually, even if they take out some guards.
2. Monster Huntress
It's a strange world, and most likely one created as a result of "A Wizard Did It". The monsters... are all sexy monstergirls. Yes, even oozes and such. Unfortunately, they have a habit of preying upon men or causing the usual monster-related problems. And so, an adventuress steps to the plate. Her plan is to find them, one at a time, beat them in combat if she must, and either sate their lusts with her own body so that they stop, or punish them good and proper to scare them off. And sure, sometimes she might lose, and they'll enjoy her body.