I’m a straight guy with a wedgie fetish. I don’t know if it’s some holdover from a picked-on childhood, but nothing gets me hotter than underpants, preferably white cotton, jammed up in my butt crack. I recently tried on a pair of my girlfriend’s thong underwear, and it was incredible. I would really, really like to buy a few pairs to play with during sex. My girlfriend is nominally aware of my wedgie thing, but we haven’t really done as much play around it as I would like, and I’m worried that she’ll think it’s a cross-dressing thing, which I don’t think she’d be into. It isn’t, but I don’t know.
Well, seems like the only way to find out is by asking. Maybe, though, you should invest in some thongs of your own before you break the news. Whether she gives a shit about the wedgie business, she very well might be annoyed to hear you have been trying on (and stretching out?) her possibly costly underthings. I would be irritated with anyone pawing through my panty drawer without my permission, regardless of however many important sexual revelations came of it.
I can’t imagine that she would mind indulging your interests, though, once you lay it out for her. A wedgie fetish falls into the category of “not something everyone is necessarily into but no skin off their teeth to do it for someone else.” Unlike, say, being hot for choking someone out or shitting in his or her mouth, there’s very little buy-in required on her end to make this happen for you. I would go so far as to say that unless she has some personal reason why giving wedgies is uncomfortable, she’d be kind of a dick not to go for it.
If for whatever weird reason she finds the thong off-puttingly effeminate (not that there’s anything wrong with effeminacy; it’s just not everybody’s cup of tea), I bet there are all kinds of European swimsuit options that you could explore that would give you a similar sensation. Or, you could wear your thong all day under your clothes, and then come home all worked up and ready for her. There are lots of workarounds for you, is what I’m saying. In fact, I’m trying to think of an easier-to-accommodate fetish and coming up blank. Foot massage, maybe? Something where cooking a three-course meal gives you a boner? Though that is actually a problem, because you’d have to let the food get cold or have sex on a super-full stomach.
Anyway, I know that sharing fantasies and fetishes can be scary, especially if your sex up to this point has been primarily vanilla-ish, but you may find that once you start the conversation of new sex-things to try, it goes to lots of exciting places. Even if your girlfriend doesn’t have any preferences or interests strong enough to be called “fetishes,” she may well discover that she’s had things she’s wanted to try out but never really been in the right spot to do it.
Hell, if either of you are into role play at all, it seems to me that wedgies would be a great entrée into the world of light submission/humiliation play. Who knows where this could lead? But the point is that sex is fun, and you should do what makes you happy.