Did John Legend Cheat on Fiancée Chrissy Teigen?

Say it ain't so, John!

Did singer John Legend cheat on his fiancée Chrissy Teigen? The New York Post claims Legend was caught kissing a blonde woman in her late 20s in the bathroom of hot spot Acme on Friday night.

“They were in there a couple minutes,” a source allegedly told Page Six, claiming the blonde woman in question was bragging about her and Legend's “steamy make-out session.”

Teigen -- a Sports Illustrated swimsuit model who is known for her hilarious tweets almost more than for her gorgeous looks -- took to Twitter to defend her relationship.

"Just read John cheated on me and in the uber-credible Post. I'm just heartbroken as it's definitely not typical post bulls--t," the 27-year-old posted. "The @nypost is normally so kind to me. And I am normally not the one to use the term s--t rag so I guess we're both a little off today."

The supermodel continued: "Gonna buy a parrot for the sole reason of it sh--ting on the post every day. Also the singing and companionship."

If Teigen doesn't believe the rumor, we guess we shouldn't believe it either. Funny, though, that on Monday night Teigen tweeted: "I honestly think so many more of us would get along if you didn't want to f--k my fiancé."

Legend, 34, couldn't have seemed happier about his pending nuptials when he chatted with "omg! Insider" correspondent Michael Yo last week.

"Yeah, it'll be a destination [wedding]. It was gonna be destination either way. We just changed destinations. So, the only reason why there was any uncertainty was we were making sure we wanted this particular place. Then we got a date that worked and now we know where it is and when it is," Legend said as he kicked off Yahoo!'s On the Road series.

In fact, the "Who Do We Think We Are?" singer even hinted at a possible wedding song.

"There's a song on my album that actually could be pretty good for the wedding. It's called 'All of Me' and it's inspired by Chrissy. She loved the song and cried when she heard it," he revealed.

Legend and Teigen have been dating for nearly seven years and have been engaged since 2011.

Regarding the cheating allegations, omg! reached out to a rep for Legend for comment, but has yet to hear back.

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