Afroman: The 'Because I Got High' singer was performing in Mississippi in February when a young woman made her way onto the stage and began dancing behind him. After ignoring her for a minute or so, he very suddenly spun round and punched her in the face, causing her to fall to the floor. He looked at her for a moment, readjusted his guitar, and went back to playing. Footage of the incident makes for a pretty chilling watch.
Martin Shkreli: He's not a musician, but Shkreli has weaselled his way, unwelcome, into the music world by buying the only copy of Wu Tang Clan's Once Upon A Time In Shaolin album. The entrepeneur became the "most hated man on the internet" when his company bought the license for AIDS drug Daraprim, before raising the price by a despicable 5,455%.
Natalia Kills + Willy Moon: That girl is a problem. During her ill-fated stint as a judge on X Factor New Zealand, Natalia Kills accused one of the contest of copying the style of her fellow judge, and husband, Willy Moon. "You make me sick," she told him, in a bizarre and truly unpleasant diatribe, before Moon joined in: "I feel like you're going to stitch someone's skin to your face and then kill everybody in the audience." They were both fired.
Noel Gallagher: Where to begin. Gallagher called One Direction "cock suckers", criticised Arctic Monkeys for wearing "skinny jeans and eyeliner" (heaven forbid any musicians deviate from traditional masculinity) and then said, "What I want, genuinely [from a rock star] is someone with a fucking drug habit."
Ten Walls: In a Facebook post he's subsequently deleted, the Lithuanian producer compared LGBT peopel to paedophiles, saying that in "the good 90s... these people of a different breed were fixed." It continued in that hateful vein, and he was promptly chucked off the bill by most of the summer's festivals.
Travi$ Scott: The rapper and producer was performing at Houston's House of Blues when he told the crowd, "I ain't cool with none of your faggots who just sitting here looking like a bunch of queers. You wearing a fucking La Flame shirt, mothafucka. You better act like it, bitch." He subsequently issues the most half-hearted apology of all time, saying he got "excited."
Jason Aldean: Apparently, the country star didn't get the many, many memoes that blackface hasn't been remotely acceptable for about fifty years. Aldean donned blackface while dressing up as Lil Wayne fo Halloween, and subsequently refused to apologise.
Kanye West: One of the few entries in this list that we don't agree with, but given the vitriole his Glastonbury appearance engendered, we couldn't leave him off. A petition to have him replaced by a "rock band" gained 136,000 supporters.
Vic Mensa: One of the lyrics in Mensa's Kanye West collaboration is, "If she bad I might hit a bitch in the elevator like Ray Rice." It referenced footage of the American football player punching his girlfriend in a lift, before dragging her unconscious body out.
Justin Bieber: Despite the fact that his new album has some genuine bangers, it's still fun to make Justin Bieber into a villain - and he's not managed to completely shed that image this year. Throwing a strop on-stage recently didn't help.