THE days are gone of groupies throwing themselves at stars in clubs and bars, hopeful of being singled out for sex – nowadays such hook-ups are sorted on social media.

All a celebrity needs to do to set up sex with a fan is private message them on Instagram, WhatsApp and Twitter — “slide into their DMs”, as it is known.

Bored in their hotel rooms, randy stars are exploiting Instagram’s “explore” option.

This shows a selection of photos, mostly of strangers, based on similar posts they have liked previously.

For any horny pop star or footballer, this is likely to mean a menu of stunning girls in their smalls.

Simply scroll through this virtual booty buffet, pick one you like, then send her a direct message.

For wannabe groupies, the unfettered access to their favourite celebs has been a game changer.

Yet for celebrity publicists and agents, who could once protect their clients from gold-diggers and kiss-and-tells with the help of bodyguards and VIP bouncers, it has been a nightmare.

One veteran agent said: “It used to be possible to keep an eye on the sort of women your client was surrounding themselves with and do some damage control. Not any more.

“They’ve got access to these girls 24/7 and there’s no way for us to vet them. These young lads can’t believe how easy it is . . .  but they’re playing with fire.”

With the added ease of accessibility comes added danger.

That girl who caught your eye might message you back, or she might make your sleazy messages public for the world to see.

The latest celeb to get caught with his virtual pants down is 22-year-old Adam Collard, from Love Island — and the Geordie hunk wasn’t even famous at the time.

We revealed this week how the personal trainer begged a 17-year-old schoolgirl he had found on Instagram to meet him at a hotel for sex before he entered the reality show.

He told her: “Age is just a number, isn’t it? You’re legal aren’t you?”

Of course, the higher your profile, the less likely you are to have to resort to begging.

Kem Cetinay, 22, said he has been inundated by girls messaging him on Instagram since he won last year’s Love Island.

He said: “It happens all the time. Some naked pictures, some hellos, some, ‘Can I take you out?’ It’s constant. I don’t reply.”

Plenty of celebrities have been left red-faced after their sleazy messages were made public.

Hollywood actor James Franco used Instagram to track down a 17-year-old Scottish schoolgirl he had met outside a stage door and nagged her for a hotel tryst.

Rugby ace Danny Cipriani swapped naked pictures and X-rated video calls with a sales manager he spotted on the same platform, behind the back of then-girlfriend Kelly Brook.

And married boxer Amir Khan has turned sleazy social media seduction into an art form.

Among those he approached on Instagram was model Emma Bond, who he asked “u a good naughty gal? Or bad naughty gal?”, and graduate Amy Lee, who he messaged: “U got any naughty pics or vid?”

The element of danger does not seem to put off sex-mad stars — in fact, according to behavioural psychologist Jo Hemmings it may fuel their addiction to the chase.

She explains: “It’s a high risk for celebrities, but there’s a sense of entitlement and opportunism there.

“Pulling women off Instagram feeds their ego. Celebrities see these women as a supply, a perk of being famous.

“Sex proves they have made it, it’s feeding their ego. But like any addiction, you need more to sustain the pleasure in increased dosages.

“The emotional detachment from what’s going on feeds narcissism.”

Jo adds: “Some of these girl fans are very determined and it’s as much a notch for them as the celebs.

“Shag and brag is a risk, and for some of them it’s what they’re after.”

Problems start when a celebrity starts sending sleazy messages to a woman who most certainly has not asked for it.

One Premier League player, who we cannot name for legal reasons, was bored one night while staying at a top London hotel with his team-mates.

He browsed the hotel’s location tag on Instagram until an attractive girl caught his eye, posing with an afternoon tea at the same hotel. Assuming she was staying there, he messaged her to ask her room number.

The woman, who was actually five miles away at home, was disgusted by the married father-of-two’s advances and sent him a fake room number to teach him a lesson.

She said: “The fact that he even contacted me, a stranger, completely out of the blue makes me wonder how many times he’s done this before.

"He lives up to that reputation that footballers seem to get — that they can have anyone on a plate whenever they feel like it.”

Another woman The Sun spoke to was bombarded with Facebook messages from a well-known soap star who is in a committed relationship.

When she refused to send him snaps of her boobs he begged to see her assets in person.

His harassment got so intense she blocked him and even considered calling the police.

She said: “What began as a few casual messages had become creepy and sinister. I was frightened of him, and the way he wouldn’t take no for an answer.”

Celebs can start to see their social media feed as a catalogue of women they could have sex with and it does not occur to them that the women might not feel the same.

Relationship expert Pam Spurr says: “Feeling untouchable undoubtedly leads to celebrities being caught out in the Press for sending these sort of inappropriate messages.

“The rest of us wonder why would they risk leaving an online trail of their dodgy behaviour? It’s because they think they can’t be touched.”

It leads some down a very dark path too. One top footballer, who is in a relationship and has children, sent explicit pictures of himself to a girl he had spotted in her school uniform.

The 18-year-old student tracked him down on social media and he sent her unsolicited snaps of his manhood.

The internet has broken down boundaries between famous people and their fans.