I wonder what it means to "be a virgin"? The oldest root of the word (virga) seems to describe a young shoot or young sprout. The earliest meaning beyond botany was "fresh and unused." The historic meaning was "chaste, unmarried and pious."
Perhaps at one time that only respectable sex, at least the only sex that you'd want to admit it, was penile-vaginal intercourse. So, okay, there's a "bright line" test: if you've been involved on either side of the P-VI routine, you've checked "lose virginity" over your bucket list. But what do we make of the effects of some large, throbbing, perhaps day-glo artificial phallus and the various portals that might welcome it? Does it matter whether she or He is operating the device, or whether penetration is a matter of her whimsy or His direction? Or the always popular penis-gone-a'wandering?
Philosophically,
S.