Here's an idea that's absolutely nothing out of the ordinary. Or, well, by my standards, anyway.
Basically, I have a think for relationships with a small but significant age-difference. A young girl - eighteen , or thereabouts ( I almost wanted to say "barely legal" but it's too much of a porn cliché ), preferably not yet in college - and one in her mid-twenties. Way I imagined it would have them meeting over the internet, getting to know each other before deciding to take the next step and actually meet. At this point, I would prefer they discover they already know each other. They could be sisters, but that seems implausible to me. The younger one being a friend of the older girl's sister, who would probably either be a closeted homosexual, or bi-curious. I'm open to other suggestions as well, though, so don't feel limited.
Bondage is optional, but always an on.
It's no more complicated than that - at least not at this stage. I love throwing twists into the mix ( the more unexpected and unusual, the better ), so don't hesitate to suggest your own, and more will surely be added as the story progresses. If that sounds good, why not let me know? I'm no mind reader, after all!
Imagine what you could do with powers like that, though ...