"Marvel Comics is introducing a new Muslim Female superhero," O'Brien -- or someone on his team -- tweeted. "She has so many more special powers than her husband's other wives."
Even though the tweet was quickly deleted, a screenshot of the tweet made its way around the social network. The response was swift, and it wasn't pretty.
"Real classy bigotry, @ConanOBrien," wrote one. "Did you enjoy having a laugh at the expense of the marginalized?"
"Her superpower is actually combating islamophobic misogynistic, pasty assholes so I can see why you're threatened," wrote another.
Marvel announced the first story of the new Ms. Marvel, Kamala Khan, a 16-year-old Pakistani-American teen from New Jersey who discovers she has shape-shifting powers, earlier this month.
The change follows the elevation of the former Ms. Marvel, Carole Danvers, to Captain Marvel, and has been extremely well received: "Captain Marvel No. 17," which introduced Kamala, is already sold out and getting a second printing.
So far, no response from Team Coco.