John Mulaney lived in Jimmy Kimmel's guest house when he was 'between lives' after rehab. Kimmel joked that 'it was like we'd adopted a son.'

• John Mulaney lived in Jimmy Kimmel's guest house for weeks after a two-month stint in rehab. 
• Kimmel joked that while Mulaney was living there, it was like he and his wife had "adopted a son." 
• Mulaney said the accommodations were "not bad" and included a Peloton bike and an espresso machine. 

After a two-month stint in rehab between the end of 2020 and the start of 2021, John Mulaney stayed in Jimmy Kimmel's guest house for weeks at a time, which Kimmel said felt like he and his wife had "adopted a son." 

In a conversation on "Jimmy Kimmel Live" Tuesday, Kimmel told Mulaney he was "curious" about how the comedian ended up staying at his house. 

"At that point did you feel like you couldn't trust any of your other friends?" Kimmel asked, seemingly referring to the "12 comedians" Mulaney said staged a surprise intervention that led to him entering rehab.

Mulaney said no, that he still trusted his friends, but admitted he finally took Kimmel up on years-long offers of staying in his guest house that's "always open," which Mulaney said Kimmel often offers to his dinner guests. 

"Most people have homes, so they take that and go, 'Oh, Jimmy, you're a mensch,'" Mulaney said. "I must have filed it away, so I was in rehab, then I was in a sober living situation, and then I was coming to LA, and I called you, and I said, 'Hey, I'm between lives. You've always mentioned this guest house...'"

Mulaney continued: "I was thinking like, 'I'm gonna call his bluff. He's said it enough times. So I lived in his guest house for a few weeks and another few weeks." 

"It was like we had adopted a son," Kimmel joked. 

Mulaney said he was "treated so well" while living with Kimmel. He joked that he "never saw" the late-night host, but he'd "wake up, and there'd be, like, a basket with bagels."

"He was like my sugar daddy," Mulaney joked of Kimmel, adding that his house was complete with a "restaurant-quality espresso machine."

Kimmel recalled that Mulaney asked to use his gym while staying in the guest house, something Kimmel said he rarely uses. 

Mulaney said he was still smoking a lot of cigarettes and was very out of shape, but that he used Kimmel's Peloton and even had to squeeze into his wife's cycling shoes to use the exercise bike. 

But he said he would "start a Peloton workout and be winded so quickly" that he would stop them after only a minute or so.

Because Kimmel could hypothetically see the saved workouts on the bike, Mulaney said he would keep the workouts playing while he sat on the floor on his phone so Kimmel and his wife wouldn't see that he did a "20-minute workout, bailed after three minutes." 

"You're assuming I actually ever got on the Peloton, which is not the case," Kimmel joked back. 

Mulaney then said he also used Kimmel's workout mirror, where he saw Kimmel's "short" saved past workouts.

On staying at Kimmel's for an extended period of time, Mulaney said the accommodations were "not bad." 

"If you're thinking of having no home, it's real good over there," he said.   

Mulaney's new Netflix comedy special, in which he openly discusses his drug addiction and time in rehab, premiered Tuesday.