The internet is blasting a man who told his wife to "lighten up" after a co-worker joked about him being unfaithful in their marriage.

On Reddit, the man explained that the uncomfortable situation began when he introduced his wife to his male co-worker.

"He has never met her," the man explained in his since-deleted Reddit post, adding his colleague "jokes around often" and quipped, "I thought Alexis was your wife," referencing another co-worker.

The man's wife didn't find the joke funny.

Noticing her energy change, his co-worker immediately "got serious" and tried to reverse the uncomfortable moment by saying, "I'm kidding. Nice to meet you."

When the couple got home, the man's wife pressed him about Alexis.

"She then asked me, 'So, what's that all about?' I asked her if she was serious and [said] it was clearly a joke, to lighten up a little," the man explained.

His response didn't help.

"She said to never laugh at things like that. I thought it was a harmless joke. Needless to say, she wasn't happy," he concluded.

In the comments section, Reddit users defended the wife's reaction and questioned the "creepy" joke.

"Yeah, this is ... creepy to your wife. And to Alexis. And if there's a running joke at work about you and Alexis, you need to wind your neck in. Your co-worker is creepy and inappropriate," one user wrote.

"That's a lighthearted joke if your wife already knows Alexis. If she doesn't, it sounds like you're flirting with someone at work so much that it's become a running joke around the office. Obviously, she's upset. Even I, based on this story, am wondering if you're sleeping with Alexis. Jokes like that don't get made with no basis. If they did, they wouldn't be funny," someone else wrote.

"What kind of healthy relationship partner makes jokes about how they want to bang someone else? Unless it's about like an actor or something. They obviously don't have an open marriage," someone else chimed in.

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