But this proved to be just the beginning, he said. “On more than one occasion, I have been sexually abused on G. I thought that was the thing that happened when you put yourself in that position. I took it as just the negative side effect of getting high, and thought that if I said anything about it, no one would believe me because I’d taken the drug either voluntarily or openly.”

However, he explained, this was not always the case. “The times I know it was introduced into my system via lube was because I went under [unconscious] without having taken anything and still felt those effects. I was then sent photos on a gay dating app of me being fucked by two men I didn’t know.”

He has kept it secret since then. “This is the first time I’ve ever admitted this because I’m too ashamed of letting myself get in that situation … I would never dream of letting people know.”

The impact of the crimes has been profound and long-term, he said. “Now I don’t trust many people. I have a major problem when I’ve dated new people because I feel like trash. Sex doesn’t have the same appeal as it once did. And if I do have sex, I have to get blind drunk to be able to have it happen. I cannot face being naked and sober with someone.”

This has left him contemplating using drugs such as GHB again in order to overcome this.

“Sometimes I think maybe if I do drugs again, sex will again be ‘exciting’ because I know that’s what a lot of twentysomethings are doing,” he said. “Even though I know people who have died [from GHB], I still think about doing it because I feel like that’s probably the only way I can enjoy sex again.”

The practice of administering drugs anally is itself not new. Both medication and prohibited substances have for decades been taken as suppositories. In the context of chemsex, however, it is chiefly crystal meth (also known as T or Tina) that has been known to be sometimes taken anally — mixed with water and dispensed through needleless syringes — and referred to as “booty bumps”.

The practice of mixing G with lubricant, however, has prompted surprise and concern among sexual health organisations, in part because of the localised damage it could do to the rectal area because GBL, in particular, is an industrial cleaner for alloy wheels and so is highly toxic and abrasive.

“GHB/GBL can irritate the skin or the mucous membrane which lines the anus and rectum, so application in lube could increase the risk of acquiring a sexually transmitted infection,” said Monty Moncrieff, the CEO of London Friend, an LGBT health charity. Hepatitis C infection, for example, is a particular risk if syringes are being used anally by more than one person.

Worse, said Moncrieff, was that “The effects of the drug could cause the person to become unconscious, meaning they may not feel pain if any damage is caused by someone continuing to have sex with them.”

The law is clear, however. “If somebody has administered a substance with the intention to overpower you in order to have sex without your consent, then that is a criminal offence for which they can be prosecuted,” he said.

There are certain measures that might be helpful if meeting people for sex, said Moncrieff, such as “always having your own supply of lube in individual sachets or maybe pop some into travel-size liquid bottles that are easy to keep with you, and making sure you only use your own”.

If you witness someone unconscious on G, “Don’t let other people carry on having sex with them – this would be classed as rape as they are not legally able to give consent; make sure they can breathe, and call an ambulance if you are worried about them.”

And if you have been assaulted, he said: “You can report it to the police, who can refer you to a specialist sexual assault centre, like the Havens in London. They can help gather forensic evidence and provide you with emotional support, even if you then decide not to press charges. They also take self-referrals.”

Although difficult, it is vital that such things be discussed publicly, said Moncrieff. “As gay men, we know what it’s like for our sexuality to be criminalised and stigmatised, and we’ve fought hard for the right to have consensual and adventurous sex without shame. But we also need to be able to address the unacceptable aspects of sex within our communities and call out this predatory and nonconsensual behaviour that we’ve sadly become aware is happening for what it is — assault and rape.”

Indeed, the method of applying G through lubricant is just one cause for concern amid a wider landscape of crime committed in chemsex settings. Stephen Morris also identified several other instances of offences manifesting in such situations.