The actor, 34, who was promoting his R-rated comedy Sausage Party, was asked by host Andy Cohen to compare the two men's packages. Rogen luckily examined the photos ahead of time so he was prepared for the unexpected request.
"As soon as I hear there is a famous penis out there, I am the first person to ravenously devour it online," he told host Cohen and fellow guest, Today show's Willie Geist.
"I've seen Justin's before, so maybe I was just like, 'I've been there, done that' a little bit. And it's a wonderful one!" he continued. "But Orlando's, I was really happy with. Good for him! He's in great shape overall. So I thought, honestly, Orlando's probably a bigger guy, and proportionally, his penis looked to scale, which makes me think overall it's probably bigger."
"[Orlando] finds the whole thing amusing," a source told Us Weekly of the situation. "This isn't something that would annoy [Katy]."
Pics of Bieber's package went viral two days later. The "Sorry" singer, 22, um, didn't appear apologetic for stripping down while vacationing in Hawaii with two models.
Just as they did with Bloom, the New York Daily News posted the snapshots with a black bar across his privates. Last year, Bieber threatened legal action against the publication when it published naked photos of him vacationing in Bora Bora.
Watch Rogen discuss Bloom's and Bieber's bulges in the video above.
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