27 here, still got my v-card. No religious or appearance based reasons (that I know of...). Basically boils down to a combination of a lack of interest, of luck and of self-esteem and confidence.

When I was a wee lad (by that I mean early to late teens), the girls I liked just went interested in me like that. Spent a good deal of time in the friendzone as a result. During that time, one such girl, a good friend but never more, told me quite casually that I had zero sex appeal (after she asked me about herself and I admitted she was sexy). That comment still haunts me to the day despite how small it might seem. Kind of enforced by my never noticing anyone taking notice of me. People have said this isn't the case, and I just miss it, but I struggle to believe them.

Following school, any interest in a relationship plummeted. I was happy to to spend my time with hobbies and friends. Eventually, when I picked up a language as a hobby, I started hanging out with friends less, the hobby taking priority. I've always been an introvert, but I retreated pretty deeply into my hobbies (aside from the language, gaming, anime and other nerdy stuff) during this - only really had the occasional work function/hang out for social interaction.

That led to a reduction in my communication skills and confidence around others. I'm not the sort of person who can strike up or hold a conversion with strangers. Need months, sometimes years, before I can really open up. Because of that, something casual is impossible for me, nor would I really want to go down that path. Not saying it's bad, at all, just not for me.

Only now am I realizing that I would like to experience a relationship, and what comes with it. I've started exercise in the hopes of making up for that lack of sex appeal with a more presentable body than I currently have. But it really comes down to confidence and self esteem. Both are in short supply at the moment, so unless I can find a solution to that, I'll be holding onto my innocence for the foreseeable future.