Can you keep a secret? Well, that's the point if you want to be a member in some social media circles.
Facebook has tens of millions of groups, many of them secret groups that you don't even know about.
Which makes it tough to find out what some Facebook secret groups are all about if you're not even supposed to know about them.
There are three types of Facebook groups: open, closed and secret. There are tens of millions of them with no breakdown of how many are secret - those groups aren't even searchable and a member has to invite you to join. Topics range from parenting to health & fitness to more personal things like sex and relationships.
In Mauritius, most of the secret groups are about sex and swinging.
In one particular group, some of them even use the old bartering system in exchange for sex. So if you want a driving lesson from someone in exchange for half an hour with your body, you can just go online!
We've actually met one of them: Melissa* is not a sex worker. She doesn't have sex with strangers in exchange for money, and she doesn't stand on a street corner at night waiting for clients. But she did recently spend half an hour having sex in exchange for free gardening and plumbing work.
The thing is, her salary doesn't cover certain things she wants - like a marble coffee table, bottles of whiskey, a washing machine, or a nice garden.
Melissa also loves having sex - as long as she gets to choose her partner, of course. She, and a growing number of Mauritians, are combining the two by trading goods and services for sex.
* Name has been changed.