Does a used sheet of paper become blank again if you don't write anything on it for a year? Would music feel "new" if you contrived to keep music out of your life for a year?

I have thought quite a bit about this, in the course of a year of abstinence. It's like putting the bike away until reflex and technique accumulate a layer of rust and dust. Once you get your feet back on the pedals, you pick up where you left off, perhaps with some aches as the atrophied muscles redevelop. Only when you pay attention and/or take new risks, rather than letting reflex autopilot the experience, does the wonder and mystery reappear. That's a function of mind, not of time. New positions, trappings, and partners may inject a sense of novelty, but sex itself will never be a "new" experience again.

So, short of amnesia, virginity does not "regenerate". The funny thing about experience is that it marks you forever. "The first time" is that, and only that; I hope I don't have to explain why "the first time in a year" is not the same as "the first time ever". The word "virgin" already has a well-established meaning, and the phrases "born-again virgin" and "virginity reversion" are oxymoronic in the context of that meaning. You can rearrange your personal definition of "virgin" in favor of some cumulative function of time, but I think the significance of the term is weakened that way.

That said, yes, I'd like to re-experience the wonder and mystery of "discovering" the seashore, chocolate, Mozart, wine, or sex, as if it (or I) were new, "virgin", unexplored. I'm not about to swear off chocolate for a year or two in hopes of re-experiencing some mystical chocolate-cherry-popping kick. The nature of mind constrains us to find wonder in the familiar by exercising attention, weaving the familiar into contexts of the ultimately wondrous: procreation, sharing, play, communion, solace, divinity - not by feigning alienation.