Authors spend a lot of time - whether before, during, or after the first draft (Hi my pantser friends!) - building a character’s backstory. Other than determining if the character has ever had sex before, not as much of this tends to be focused on the sexual history of the characters.
As with so many of the things we are discussing, backstory is seasoning. In most cases, more of your story – at least the parts you share with the reader – is focused on the now. But spending time thinking through some of this can be useful in creating fully rounded characters.
Some examples to consider include –
Is this the first time the character is having sex? (Assuming there is sex in your story, which there may not be.)
Where would the character have learned about sex? Do they have a parent, sibling, and/or trusted friends who would have given them information?
How accurate is the information they’ve been provided?
Has the character previously experienced either a pregnancy and/or sexually transmitted infection (STI) scare? Or experienced pregnancy and/or STI?
If the character has had sex before – how carefully did their partner(s) treat their concerns about pregnancy and/or STIs?
Has the character had bad sex before?
If the character has had bad sex, did they learn how to advocate for themselves sexually?
There is no right answer to any of these questions. And as I mentioned before in many cases the answers may not ever make it onto the page of the story you are crafting. But it can be useful to consider them.
As a Segway, let’s touch on something else.
Virginity is a construct.
Let me repeat myself. Virginity is a construct. There is no entirely agreed upon definition of virginity. (There are tons of studies where teens who take purity pledges still engage in anal and oral sex.) Most of the generally agreed upon definitions apply only to heterosexual couples. Also there is literally no way to determine virginity other than asking the person about their sexual history. The ways the body changes during sex often revert to their pre-sex state within a fairly small period of time.
Your characters may exist in a world where there is an agreed upon definition of virginity. If so, what that definition is may be unclear to your reader unless explicitly stated.
The same is often true of characters who have been dubbed some term that essentially means known to have dated and probably had sex. I’ve been rewatching “ER” and it’s fascinating the characters the show is trying to tell me are untrustworthy or unreliable to date, when if you add up hookups and love interests, the show’s main characters run pretty even.
So understanding what metrics and also if they are fairly applied helps the reader better understand the both world your characters are operating in, and how the characters feel about that world.