I've been craving a kidnapping plot lately - I was thinking that it would go something roughly like this.
My character, Jasper, would be a wealthy young man whose father is a drug lord. Jasper's father is incredibly wealthy, and incredibly influential, but has many enemies. I'm thinking that one of those enemies could hire someone, your character, to kidnap Jasper and hold him as a bargaining chip. Jasper's father would be furiously trying to negotiate for his son's safe return but in the meantime he'd be kept somewhere dark, shut away from the world. The only person he'd see would be your character, and over time (I'm thinking that it would take place over about two months, as far as the kidnapping itself went) he'd develop Stockhom Syndrome and grow to adore your character.
I'd like there to be some bondage and non-con involved, but not out-right rape. Jasper would be gay, and I think that on a deeper level being kidnapped would excite him, and he'd be attracted to your character without wanting to admit it. I'd like your character to take advantage of that. It could involve humiliation, Master/pet play, and collaring or branding. Whatever you'd like to work in, really. I'm fine with this being anywhere from fairly light to heavy in terms of bondage.