Jennifer Lopez was an open book on 'Watch What Happens Live' -- even if she was kind of forced into it.

Playing a round of 'Plead the Fifth,' host Andy Cohen fired three cringe-worthy questions at J. Lo, who gamely answered all of them. (Well, partially because she forgot she could "plead the fifth" on one.)

"Can I leave? Am I trapped in here?" J. Lo asked before Cohen began the game. "Oh my God, I'm starting to have anxiety."

If she was anxious, Lopez did a pretty good job of covering it up, considering she answered all of the questions pretty seriously -- and straight-forward.

When Cohen asked her about her relationship with Ben Affleck -- specifically, if she was responsible for getting him to dress better -- Lopez was candid in her reply:

"I did kind of like, say, 'You're a movie star! You should wear a suit! You should do this with your hair!' For sure. I mean, I do that," she revealed. "… He was into it. He didn't do anything he didn't want to do ... He had some good fashion moments when he was with me!"

And as for the supposed feud she has with Mariah Carey, J. Lo claims that it is kind of one-sided.

"I don't have a feud against her at all … I know from back in the day, I've read things that she's said about me that were not the greatest, but we have never met," Lopez said. "I would love to meet her and I would love to be friends with her. I think she's incredibly talented and I've always been a fan of hers. 'My All' is one of my favorite songs of all time. I just love her. It saddens me to hear anything that's negative because I'm a fan of hers."

Then Cohen went in for the kill: Who is better in bed -- singers, actors, or dancers?

Cracking up, J. Lo responded: "I have to say that in my limited experience," she said, laughing, "I would have to say anybody involved in music. So, singers and dancers." But when she realized she could've pleaded the fifth on that one, she was hilariously upset. "I forgot my card!" she screamed. "Dammit!"

J. Lo still expanded on her relationship with dancers, revealing:

"I've dated two dancers. One, I had a brief marriage with, Cris Judd, who is an amazing person and whom I love, and then Beau [Casper Smart], who we just broke up, who I love as well. He's a good friend."

Watch Jennifer Lopez play 'Plead the Fifth' in the hysterical video above.