I totally hear you on that one. I do the same thing with my RP partner. Though really, I don't think it would make you a shitty friend. I would think it would be a compliment. It might creep them out, but then again, you never know. Maybe the same thing happens to them and you have no idea. Which is pretty much the sexiest thing in the universe.
Clearly you should just meet up and start a relationship and have wild crazy live action roleplay sex. True story.