Readers, allow me to adequately warn you that if you’re remotely squeamish, you must mentally prepare for the sexual education you’re about to receive. If you’re grossed out by the mere thought of period sex, the notion of rainbow kissing might just send you over the edge. Because despite its sweet seeming name, rainbow kissing is perhaps the least romantic sexual act one can fathom.

What is rainbow kissing? Allow me to explain. A rainbow kiss is a sex act in which bodily fluids are swapped orally between someone with a penis and someone with a vulva — namely, semen and menstrual blood. Yes, I did warn you!

In recent months, searches for ‘What is rainbow kissing’ went through the roof on Google. It was all thanks to a viral TikTok video in which users known as Meg and Emma (@mgly22594) discussed a message a random TikTok user had sent them about wanting to give them rainbow kisses.

‘I said, “This sounds very lovely, I do like rainbows but no thank you I don’t want kisses,’ Meg explains, unaware of it’s true meaning. ‘Do you know what rainbow kisses are?’ Emma asks, then tells Meg to look it up before showing her appalled reaction after doing so.

With 5.3million views, over 500,000 likes and 20,000 people discussing rainbow kissing in the comments, you can see where all the newfound search has come from then, huh? And naturally, with that search comes intrigue into how people actually perform rainbow kissing – and what the allure really is.

So, with that in mind, we spoke to sex and gender educator Laura Clarke (@mybodyandyours) to get the lowdown on all things rainbow kissing. Proceed with caution if you’re already queasy!

A common way that a rainbow kiss is performed is via the 69 sex position, in which two partners perform oral sex on one another at the same time. What makes a rainbow kiss different is that one partner would be on their period. After ejaculation, the partners — one who has semen in their mouth and the other who has menstrual blood in theirs — would kiss, mixing the two bodily fluids together.

Incorporating bodily fluids into sex is a fairly common kink — in more-mainstream porn this might look like somebody with a penis ejaculating into their partner’s mouth, or onto their face or chest. But it can also extend to sharing other fluids — such as spit, blood, or urine.

Rainbow kisses themselves are perhaps a little more niche, but we don’t know for sure how popular they are! Sex during menstruation is still a taboo within our society (which could potentially add to the playful “naughtiness” of the act) so it’s likely that more people are engaging in sex acts like these on the down low (pardon the pun!). It’s obviously important to say that rainbow kissing isn’t for everyone, and you should never be pressured into trying a sex act that you don’t feel 100% comfortable with.

Discussions around rainbow kissing date back to at least 2002, but it’s extremely likely that performances of the sex act itself go back way further. There’s no real consensus on where the term itself came from, but rainbow kiss discussion has had a resurgence online this year.

A recent TikTok trend involved people filming themselves before and after searching the term ‘rainbow kiss’ and documenting their shock. This is probably a good time to remind people of the phrase ‘Your kink is not my kink, but your kink is okay’ — just because something isn’t for you personally, or even grosses you out, kink-shaming is never okay!

First of all, everyone needs to be of age and enthusiastically consenting! Secondly, all sex acts with another person carry a potential risk of sexually transmitted infections (STIs). Because it’s not possible to achieve a rainbow kiss while using a condom or dental dam, you need to be confident that everybody involved has been tested recently and has no STIs.

A good rule of thumb is to get tested every time you change partner or, if you’re in a long-term monogamous relationship, every 3-6 months. Rainbow kisses should also be avoided if you have any cuts, sores or ulcers in your mouth, or bleeding gums, as this increases the risk of infection, including HIV.

Similarly, if you are immunocompromised, it might be a good idea to give rainbow kissing a miss and stick to oral sex with a condom or dental dam. Avoid brushing your teeth before oral sex, as this can create microtears in the gums which can make you more susceptible to infections. As with any kink, practice RACK (Risk-Aware Consensual Kink) and know that while you can never completely eliminate risk, you can take steps to reduce it.

To find out more about RACK, follow Laura online at @mybodyandyours on TikTok, Instagram & X.