'What's worse: When a guy gets a boner during a sex scene or when he doesn't?'

By Nick Maslow
March 10, 2017 at 10:07 AM EST

Actors have long insisted that shooting sex scenes is drastically different than the real thing, but all the cameras, lights, and crew members aren’t always enough to prevent one aspect of human nature: male erections.

Allison Williams and Samuel L. Jackson shed light on the phenomenon Thursday when they appeared on Bravo’s Watch What Happens Live with Andy Cohen, and it turns out the actors have completely different takes on the topic.

The hilarious exchange began with Cohen asking a viewer’s question: “What’s worse: When a guy gets a boner during a sex scene or when he doesn’t?”

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“We debate this a lot,” explained Williams, whose Girls character Marnie has been sexually active throughout the HBO show’s six seasons. “Because it is flattering but upsetting when it happens, and it is also upsetting and unflattering when it doesn’t happen. So the best case scenario is kind of like a suggestion of excitement without the actual physical manifestation of it.”

“Oh, bulls—,” responded Jackson. “Bulls—.”

“Dead serious,” replied Williams. “It is so awkward, trust me.”

“Do they wear socks?” asked Jackson, referring to an item male actors wear to cover the essentials when they go nude in front of the lens.

“Yeah, they have to wear the little sack thing, yeah,” said Williams.

“See, I always apologize first,” said Jackson. “I’ll say, ‘I’m sorry if I do and I’m sorry if I don’t… That generally works.”

Cohen wanted to explore the subject even further, asking Jackson, “Do you typically get stimulated in that way or?”

“I don’t do sex scenes that often,” Jackson clarified. “I’ve only done about three in my life.”

Laughing, Williams quipped, “We found the one way I have more experiences than you.”

Watch the stars dish on their experiences in the video above.