Drugs in Hollywood aren't shocking, but it's still shocking to hear that some of your favorites may be accused of partaking in them when they maintain relatively squeaky clean reputations. Case in point: An alleged drug dealer to the stars has been exposed in a U.K. tabloid sting, and Rihanna, Justin Bieber and One Direction's Zayn Malik and Liam Payne were listed as his associates.

U.K. newspaper The Sun established an elaborate sting operation to expose Leon "Starino" Anderson, who's been spotted out and about with Rihanna, Malik and Bieber, as well as Chris Brown, Nicole Scherzinger, Diddy and various other celebs and supermodels (including Cara Delevingne, who was rumored to date Harry Styles).

Anderson claims to be a "good friend" to lots of boldfaced names, but the Sun claims he's actually a drug dealer and even a pimp.

“It’s part of my service," he revealed to the tab's undercover reporters about his drug runs. "I have to. I have to be able to (get drugs). I have the biggest clients in the world."

“I am their right-hand man," he added. "When they’re in London and want to go out, I arrange everything from restaurants and clubs to anything else they want.”

Anderson spoke about Bieber specifically, telling the tab, "He was hard work. He likes to party and he likes his girls. In the end it got too much. He wanted me to go everywhere with him and carry Class A for him and I thought, 'I ain't going to jail for no one.'" (For the uninitiated, Class A is what the U.K. classifies as hard drugs -- think heroin, cocaine, etc. -- as well as what Ed Sheeran sings about in 'The A-Team!')

Anderson informed the reporters he could nab prostitutes as well, telling the writers, "I have got the best girls in the world working for me. So if you want to f--- some of the best girls in London, I can arrange it. I can also take you to a top lap dancing club which is discreet, nobody will give you trouble. I take some of my clients."

If Anderson's name sounds familiar, it may be because he was involved in Malik's cheating scandal with an Australian waitress earlier this year.

Of course, Anderson -- and the celebs with whom he associates -- is innocent until proven guilty, and just because he hangs around with famous faces doesn't necessarily mean he's supplying all of them with vice. However, the Sun have turned their findings over to authorities ... so you may well hear a lot more about Anderson and his friends in the future as investigations go down.

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