I know that's not what you meant but it's still true.
I've been dating basically the same guy in every relationship I've had. Even though they all seem "different" at first I can give a pretty accurate profile of a guy just based on the fact that there's a mutual attraction and we seem to be headed towards a relationship. The one exception to that rule was this wonderfully kind and considerate man who lavished me with attention, respected the heck out of me and gave me the freedom to be myself. He drove me nuts and I never really did feel any chemistry with him.
The thing with C was that I knew he had some of the... some might call them character flaws... that I seem to be drawn to and he was very much aware of them. I thought that because he recognized how destructive he could be that he would also be there to clean up the mess afterward. He said he would. We actually did talk about that and I thought I'd found someone who could be cruel to me in ways I seem to need and he said he was excited about finding someone who would allow, even crave, some of the evil he could dish out. But he also said he'd be there to pick up the pieces when it was done and that didn't quite work out as planned.