Sum 41 frontman Deryck Whibley hit back at ex-manager Greig Nori’s accusation that Whibley “initiated” their relationship in an Instagram video on Tuesday. Whibley accused Nori of sexual and verbal abuse and grooming, beginning when he was 16 and Nori was 34, in his upcoming memoir Walking Disaster. “It’s come to my attention that Greig Nori has now called me a liar,” Whibley said in the video. “I tell you right now, I stand behind every word that’s in my book, 100 percent. I’m not a liar.” According to the Los Angeles Times, Whibley alleged in his memoir that when he was 18, Nori took him to the bathroom at a rave and kissed him “passionately,” beginning their sexual relationship.“The accusation that I initiated the relationship is false,” Nori wrote in a statement to the Toronto Star. “I did not initiate it. Whibley initiated it, aggressively.” He did not address the accusations of abuse. In response, Whibley spoke directly to Nori in his video. “Greig Nori, if you think I’m a liar, there’s only one way to settle this,” Whibley said. “Under oath, in front of a judge, in front of a jury. Anytime you want. I’m ready. Whenever you are.”