The first presidential debate between Hillary Clinton and Donald Trump kicked off on Monday evening, but a comment from Fox News host Brit Hume after the debate stole the conversation on Twitter.

In Fox's post-debate coverage, Hume was commenting on both Trump and Clinton's reactions throughout the debate. Hume describes Trump as looking "annoyed, put out, uncomfortable," but what his description of Clinton is what sent Twitter off.

Fox News commentator: Trump looked "annoyed, put out, uncomfortable," Clinton looked "composed, smug sometimes, not necessarily attractive" pic.twitter.com/OJFxdw4Ver — Mashable News (@MashableNews) September 27, 2016

"She looked, I think, for the most part, she looked composed, smug sometimes, not necessarily attractive."

Many deemed Hume's comment on Clinton's attractiveness unnecessary and sexist, especially in a presidential debate.

@brithume I am so glad you called Clinton out on not looking attractive. It is, of course, the #1 thing I look for when choosing a President — Robin Corak (@robincorak) September 27, 2016

Hey @FoxNews, you gonna post an apology for claiming that Hillary Clinton didn't "necessarily look attractive"? — Celine Robinson (@svuceline) September 27, 2016

Boo they had a commentator critique Clinton as "not necessarily attractive"

Like how is that even an option for a critique?? https://t.co/AnBBvhiHAL — Jaymes Vaughan (@JaymesV) September 27, 2016

Brit Hume: "the TV audience saw the faces of the two candidates... and she looked composed, smug sometimes, not necessarily attractive" — Robert Mackey (@RobertMackey) September 27, 2016

Brit Hume says Hillary Clinton looked smug and not always attractive - what kind of description is that of the Dem nominee for president? — wendy schiller (@profwschiller) September 27, 2016

@brithume I am so glad you called Clinton out on not looking attractive. It is, of course, the #1 thing I look for when choosing a President — Robin Corak (@robincorak) September 27, 2016

Because it's so important that Ms Clinton looks attractive, right? @CatherineDeveny https://t.co/pl4n4uWUPS — Alana Dagwell (@AlanaDagwell) September 27, 2016

"Trump's a liar, completely inexperienced and has no idea what he's talking about!"

"But is Clinton attractive enough?"#debatenight pic.twitter.com/MNvP1pbQRF — Fulci Girl (@Fulcigirl) September 27, 2016

Comparing faces side-by-side: Clinton "not attractive" @megynkelly u were THISCLOSE to calling him out! #debatenight pic.twitter.com/4p7S0nF7PA — Caroline Goggin (@CC_Goggin) September 27, 2016

Brit Hume apparently rates women the same way that Trump does. https://t.co/bF3rWltPKn — W.M.W (@wmweibel) September 27, 2016

UPDATE Tuesday, Sep. 27, 4:47 p.m. PT: On Fox News the following day, Brit Hume said he was talking about the candidate's demeanor when he said Clinton looked "not necessarily attractive." After commenting on Clinton's attractiveness in the original video, however, Hume prognosticated that "a lot will turn on how people reacted to the faces they saw side by side on that screen tonight."

Bonus: Trump's debate sniffles are louder than his words