I was in the pub recently when a group of 18-year-old guys I'm acquainted with referred to a girl they know as "a slut". Nine years their senior, I was feeling pretty confident and combative so decided to ask: Why? What makes her a slut? LET'S GO, BOYS.

After a few rounds with me, one laughed. "She's got us beat, lads! Stand down!" but another kept on, so I asked if I was a slut too - we're not in single figures any more, Toto. "Of course you're not! Anyway, you're with Mike now so it doesn't matter." I didn't know having a boyfriend absolved me from all previous sexual sins. Praise baby Jesus.

A friend posted the above picture on Facebook. He never did reply to my comment of course, because there is no answer. There is no number of sexual partners that means you have crossed the line from 'Look at me, I'm Sandra D' to 'The Scarlet Letter'. You've probably heard the analogy for why men and women sleeping around are different things: Everyone would love to have a master key but a lock that works with any old key is a bad lock.

It's a shitty analogy, but here's why it works.

In the words of Chimamanda Ngozi Adichie: "We teach girls that they cannot be sexual beings in the way that boys are." Women have become the gatekeepers of sex. Sex is not a mutual act between two people, but an item in our possession. The aim of the game is for men to get it from us. They're expecting it to be difficult - they've been told it will be difficult. When they meet a woman who is mutually interested in sex, she needs a label and that label is 'slut'. When the key doesn't need a bag of tricks to open the lock, it is suspicious.

I have had two periods of promiscuity in my life - one before and one after my six year relationship. The first came from the bad place of a chubby teenager with no self esteem raised in a prudish household, who didn't think guys would like her any other way. The second came from the good place of a woman in her mid-twenties leaving an abusive relationship, gaining 'happy' weight and genuinely enjoying herself before unexpectedly meeting Mr Perfect on Tinder.

Slut shaming women does a disservice to men too. I've said before that having a higher sex drive than my partner made me very depressed initially, due to being trained to think I had to be "on" for him all the time, because of the stereotype that men have inexhaustible sex drives.

The men I know who are women's allies - feminists - all have a healthy attitude to sex, whether they're having plenty of it or not. If you have nothing better to do than grade women on how slutty they are, you are probably still a confused young lad trapped in an adult's body, not knowing what you would do with a vagina even if you got near one.

I cannot judge - I have slut shamed in my time. It also took me until, basically now, to figure what's going on in my brain when it comes to my own sexual desires and needs (a post for another time). There are a lot of confused people on both sides and intertwining issues; slut shaming is integral to rape culture, victim blaming, gender stereotyping...it's impossible to see where one ends and the other begins. 

I believe that all sex, from the missionary postion right up to the people who dress up as clowns and spank each other, is healthy as long as everyone is in it for the right reasons. The next time you hear the word "slut", simply ask: WHY?