Sum 41's Deryck Whibley Reveals Sexual Abuse, Claims Former Manager 'Groomed' and 'Pressured' Him into Relationship

• Sum 41 frontman Deryck Whibley claims he was sexually abused by his former manager
• In his memoir Walking Disaster: My Life Through Heaven and Hell, Whibley claims he was "groomed" by Greig Nori who "pressured" him to be in a sexual relationship
• Nori was the band's first manager before he was fired in 2004

Deryck Whibley, frontman of Sum 41, claims his former manager "groomed" him and "pressured" him to be in a sexual relationship.

In his new memoir Walking Disaster: My Life Through Heaven and Hell (out Tuesday, Oct. 8), the punk musician claims Greig Nori, frontman of the Canadian band Treble Charger, sexually and verbally abused him over the years. The pair, who shared a "special connection" on a creative level, met when Whibley was 16 and Nori was 34, per The Los Angeles Times.

According to Whibley, he met Nori backstage at a Treble Charger show where Nori gave Whibley his phone number and the "Fat Lip" singer invited him to one of his band's performances. Nori allegedly became a mentor to Whibley and would talk for hours on the phone to him. According to Whibley, Nori gave him and his bandmate Steveo their first drinks, "which were Goldschläger shots."

Eventually, Nori became Sum 41's manager, producing their music, helping them form industry connections and inviting them to parties and raves. "Greig had one requirement to be our manager — he wanted total control,” the "In Too Deep" artist writes in the book. “We couldn’t talk to anyone but him, because the music business is ‘full of snakes and liars’ and he was the only person we could trust.”

According to Whibley, Nori allegedly "passionately" kissed him in a bathroom during a night of partying when he was 18. At the time, Whibley was confused and in shock — he had never been attracted to men before. He also claims that Nori tried to convince him that their connection was worth exploring further by pointing out that many rockers were "queer" and that "most people are bisexual; they’re just too afraid to admit it.”

"He was so relentless and convincing that after a while, I started to believe that maybe he was right," Whibley writes. While Nori allegedly never experienced same-sex attraction before either, he allegedly said that Whibley "brought it out in him because what we had was so special."

After experimenting with his sexuality for a few months, Whibley wanted to end their physical encounters. However, Nori would allegedly become rageful and call him "homophobic" when he tried to end things. "He told me this was all my fault to begin with because I should never have said yes to it in the first place. I started this and now he was in it with me so I couldn’t just stop," Whibley writes.

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While Whibley kept his alleged relationship with Nori to himself for a long time, he claims he told a mutual friend of theirs who called his experience with Nori "abuse." He later told his then-girlfriend, now ex-wife Avril Lavigne, to whom he was married between 2006 and 2009, about the alleged sexual abuse at the hands of Nori. "That’s abuse! He sexually abused you,” Whibley recalls her saying in the book.

Later, he told his current wife Ariana Cooper, to whom he's been married for 10 years, and had the same reaction. “He groomed you from a young teen and mentally forced you. You said no, you didn’t want to do this anymore, and he told you it had to continue or you would lose everything. That’s psychological, mental, and physical abuse," Whibley claims Cooper said.

Despite the alleged physical encounters ending, Whibley claims that the verbal abuse progressed as he became increasingly jealous of Sum 41's success and tried to pit the band members against one another. In 2004, Sum 41 allegedly fired him.

Nori has not yet responded to PEOPLE's requests for comment.

In March, Sum 41 released their eighth and final album Heaven :x: Hell, which Whibley told PEOPLE "encapsulates the entire journey of Sum 41."

If you or someone you know has been a victim of sexual abuse, text "STRENGTH" to the Crisis Text Line at 741-741 to be connected to a certified crisis counselor.