Getty Images North America 1 / 6
Getty Images North America 1 / 6

That's some presidential hanky panky!

John Legend and Chrissy Teigen are one of the most open celebrity couples, unafraid to discuss intimate matters of their relationship. But during an interview with "Extra!," John was at a loss for words after he and his wife were asked the most public place they've ever had sex.

"Probably the Obama thing," Chrissy said, while laughing nervously and walking away.

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Secret service, are you reading this?

As the "Extra!" host pressed on, a flustered John said, "We're not going to discuss that. We're not talking about it, that's the truth."

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The duo did elaborate a little, saying that their libidos didn't get the best of them at the White House, nor was it while Barack Obama was President, so it had to have been pre-2008.

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With her husband shaking his head incredulously, Chrissy said, "Sorry, I'm in trouble now."

Clearly, the words "open book" don't accurately describe this couple's relationship.