The Manhattan-based lawyer has worked for the president for years, well before the 2016 campaign and election. Among his apparent shows of loyalty? Cohen recently said he paid $130,000 of his own money to a porn star who had once claimed to have an affair with Trump.
While not releasing specifics as to why he made the "private transaction," Cohen has spoken in the past about his willingness to work to make Trump's life easier.
"It means that if somebody does something Mr. Trump doesn't like, I do everything in my power to resolve it to Mr. Trump's benefit," Cohen told ABC News in 2011.
"If you do something wrong, I'm going to come at you, grab you by the neck and I'm not going to let you go until I'm finished," Cohen added.
Cohen joined the Trump Organization in 2006 and has been a close employee and confidant of Trump ever since. He was a regular presence on the campaign trail, making a number of cable news appearances in defense of his friend, and regularly firing back at Trump critics online using Twitter.
In recent months, the subject of Cohen's ire has been the infamous "dossier" that was released during the campaign. Cohen said he filed defamation lawsuits in January against Fusion GPS and BuzzFeed for their role in the creation and release, respectively, of the dossier.
In both suits, one filed in federal court against Fusion GPS and the other in state court against BuzzFeed, Cohen claims that the dossier of salacious but unconfirmed allegations of collusion between members of the Trump campaign and Russian agents resulted in “harm to his personal and professional reputation, current business interests, and the impairment of business opportunities.”
Like Trump, Cohen has supported Democrats in the past, including then-candidate Barack Obama in 2008.
"It took a great man (@POTUS) to get me to make the switch," he wrote.
This isn't the first time that Cohen switched to the Republican Party, however, having run a failed bid as a Republican for an Upper East Side city council seat in 2003, according to real estate news site The Real Deal.
When it comes to his real estate needs, Cohen appears to keep it in the family.
Cohen has publicly touted the financial benefits of his investments in Trump-branded real estate in a 2007 New York Post article.
At the time, Cohen said that he bought his first apartment at Trump World Tower in New York in 2001, and he urged his parents, in-laws and business partner to follow suit.
The New York Post reported that both Cohen and his in-laws went on to buy more Trump properties: up to four apartments in Manhattan and New Jersey for Cohen, and two more New York apartments and a Florida property by his in-laws.
Cohen told the paper that Trump properties "are solid investments," and Trump returned the compliment, saying Cohen "has a great insight into the real estate market" and that "he's a very smart person."
While Cohen's public image is intrinsically intertwined with Trump, he has shared some tidbits of information about his personal life online as well.
Cohen has used his online presence to praise his "Ivy League daughter," which prompted some outcry since it was accompanied by a picture of her modeling in tights and lingerie.
Recently he announced that while he is a fan of Oprah, he doesn't think her much-hyped presidential run is going to happen.
One declaration of support came in honor of Trump's birthday in July 2017, where Cohen shared a picture of them together in what looks like Trump's New York City office.
"I stand with you every day as you work to #MakeAmericaGreatAgain for all Americans!" Cohen wrote.