Sen. Mitt Romney, R-Utah, confirmed late Sunday that he is behind an anonymous Twitter account under the pseudonym "Pierre Delecto" that he's used to be a "lurker" on social media for most of the past decade.

The account was first revealed by Slate's Ashley Feinberg, who was also responsible in 2017 for revealing former FBI Director James Comey's anonymous account.

The trail leading to the secret account began earlier Sunday when The Atlantic published a profile of Romney at a time when he is one of a few prominent Republicans to be critical of President Donald Trump's actions on Ukraine that led House Democrats to open an impeachment inquiry.

Romney was asked about one Trump tweet in particular where the president attached the hashtag "IMPEACHMITTROMNEY," to which the 2012 Republican presidential nominee said, "That's kind of what he does," and explained that he uses a secret Twitter account to follow politics.

"What do they call me, a lurker?" Romney said, declining to name the account but saying that he followed fewer than 700 accounts. That sparked Feinberg's interest, who went through the Twitter accounts of some of Romney's relatives for clues. She found that Romney's eldest grandchild, Allie Romney Critchlow, had just 481 followers, making the account ripe for a quick investigation.

It's through her account that Feinberg found a user who piqued her attention — a person under the handle @qaws9876. The account was public and followed about the same number of accounts Romney had mentioned to The Atlantic. It followed all of the Romney family, a number of Romney-related 2012 campaign accounts and political reporters from the Romney 2012 beat, among others that seemed right for Romney to have an interest in following.

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The account, which went under the username "Pierre Delecto," was public and showed only a handful of tweets, most in recent months. The tweets were often replies to prominent users criticizing the senator.

In May, Romney responded to Washington Post opinion writer Jennifer Rubin, who wrote that Romney's strategy was "non-confrontation verging on spinelessness."

"Jennifer, you need to take a breath," Delecto replied. "Maybe you can then acknowledge the people who agree with you in large measure even if not in every measure."

Romney also liked a number of tweets that were strongly critical of Trump, including one supporting the use of the 25th Amendment in response to the president's recent decisions on Syria and Turkey. Romney also liked searing criticism of former House Speaker Newt Gingrich and 2016 Democratic presidential nominee Hillary Clinton.

The account was made private late Sunday evening. Soon after, Romney told The Atlantic's McKay Coppins, who authored the profile of him, that he was in fact behind the "Pierre Delecto" account. "C'est moi," he told Coppins.

On Monday, Romney said his moniker translates to "pure delight."

"Yeah, I mean, I like what I like," Romney said of his usage of an anonymous account. "Fortunately there's not a dislike button ... I follow a lot of people as a way to keep up with the news and I followed 600 or some odd people, 700, just a way to have a private account to see what's going on."

One of Romney's Senate colleagues, Cory Booker, D-N.J., said he just found out about the account Monday morning and was amused.

"Pierre Delecto? Alright. Okay. I love that name," Booker joked on the presidential campaign trail in New Hampshire. "I've gotta find a good one (Twitter name) — somebody's gotta help me find a good one."

In an interview with "Axios on HBO" that aired Sunday, Romney said of Trump asking China to probe former Vice President Joe Biden: "We certainly can't have presidents asking foreign countries to provide something of political value."

"That is, after all, against the law," he added.

On Trump's personal life, Romney said the president "has elements, I'm sure, of honor in his life."

"And there's things that I think are not honorable. And I mention that because of the payment to a porn star for sexual relations outside of marriage," he added of the pre-2016 election payoff to Stormy Daniels, who alleged an affair with Trump that the president has denied.

"Look, I'm one of those who believes that we have a responsibility to be honorable and faithful to our wives."

Trump slammed Romney at a Cabinet meeting on Monday, portraying the Republican lawmaker as disloyal.

"They're vicious and they stick together," Trump said of Democrats. "They don't have Mitt Romney in their midst. They don't have people like that."