During the show's "Plead the Fifth" segment, Cohen asked the DNCE singer a series of probing questions, kicking off with which Jonas Brother is the most well-endowed.
While his younger brother, Nick, refused to answer the same question when he appeared on the Bravo talk show in June, the "Cake by the Ocean" singer was more forthcoming. "This is Nick's words not mine, but he said he was going to say me, so I'll say me," Joe said.
His fellow guest, supermodel Ashley Graham, just laughed in response and said, "OK."
Next, Cohen asked Joe, 26, about a song that he said he'd written that's going to "piss someone off." Who is the person, and have they heard the song yet?
"The song is not going to be on the album," the "Toothbrush" crooner replied. "I'm going to save it for a side project possibly, maybe a B-side." But when it came to revealing who the song was about, he chose to plead the fifth.
"I'll marry Demi. She's a friend," Joe said. "Shag Taylor. Kill Gigi."
Cohen admitted that he hadn't known that the teen heartthrob and Swift, 26, had dated.
"We were children, 18, 19. Young enough," he admitted.
Swift reportedly wrote the songs "Forever and Always" and "Last Kiss" about the former Jo Bro, who allegedly dumped her during a 27-second phone call in 2008. The "Bad Blood" singer also was said to have written 2010's "Better Than Revenge" about Camilla Belle, the woman Joe left her for.
"No need for revenge. Just sit back & wait," Belle, 29, tweeted on July 18. "Those who hurt you will eventually screw up themselves & if you're lucky, God will let you watch."
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