Lorre said he ran into the "Argo" star earlier in the month while the two were taking a break in the bathroom.
"Yes I peeked. And yes, Comic Con, he can play Batman," the "Two and Half Men" producer said.
Affleck, 41, took the stage later in the night and kept the joke going.
"I was at the bar briefly, and I came back to my seat and somebody said, 'You know, there was a guy up on stage who said you have a big d-k,'" he joked.
Affleck continued, "I was like, 'You know, isn't that always how it goes? The one time it happens and I miss it!' Thank you very much. Whoever you are, God bless you. I'm often confused with Matt Damon but rarely with Michael Fassbender, so it' a nice change."