While appearing on Tuesday night's "Jimmy Kimmel Live," the Grammy winner was interviewed by the former One Direction singer, who was guest hosting the show. In the wide-ranging chat, the two talked about Lizzo's career, her new chart-topping single, "Rumors," the first time they met and more.
And Lizzo, for one, couldn't stop flirting with Niall, who also joined in on the fun.
Niall, 27, began the interview by introducing Lizzo, 33, as "my beautiful woman." His guest, who appeared virtually said, "This is the sexiest call I've ever been on." Niall quickly pointed out that Lizzo was sitting in front of a bookshelf, which displayed several of her awards, including three Grammys.
The two then discussed the creative names for their fans.
"With success comes fans and you know you've made it when your fans have their own name. Your fans go by what?" Niall asked, to which Lizzo replied, "The Lizzbians. ... We're all Lizzbians!" As for the "Night Changes" singer, he said he recently learned that his fans go by the "Horan Dogs," noting that depending on "what country you come from it sounds a little bit different."
This prompted Lizzo to joke, "Oh, in America, it's a Horn Dog, okay? I think you're giving me a one erection, baby."
She went on to chat about her old job before she was famous and her time in girl groups, before Niall brought up her latest collaboration with Cardi B's, "Rumors."
Lizzo said she's "eternally grateful" to Cardi for filming the music video while pregnant, jokingly noting that "if I was pregnant I would want to sit on my ass at home and prop [up] my feet and eat some Hot Cheetos and Takis."
"I do that and I'm not even pregnant," Niall quipped. Lizzo laughed and then joked, "You want to change that?"
Niall then asked about one particular lyric in "Rumors," in which Lizzo references Drake. At one point in the song, Lizzo sings, "No, I ain't f--- Drake yet."
"Okay, so the original line was, 'No, I ain't f--- Niall yet,'" Lizzo joked, as the audience cheered and Niall took a drink of water. "The label said it was a little bit provocative. So I changed it to Drake, a safer bet."
When asked if she's "heard from Drake," Lizzo said, "I think he's heard the No. 4 song in the country," before adding, "Actually, I have heard from Drake, but that's all I'm [going to] say on that."
After the commercial break, Niall and Lizzo took a look back at the first time they met at a radio station in London.
"They introduced me to you. And you were like, 'Congratulations, Lizzo, you're smashing it.' And I was like, 'I'll smash you,'" Lizzo recalled and she and Niall burst into laughter. The pair then discussed how the word "smashing" means something different in the U.K. than it does in America.
The hilarious interview took a turn when Niall pointed out that his fans think he and Lizzo "should date," prompting the "Our Song" crooner to introduce a segment in which he and Lizzo tested their compatibility. The two answered a series of questions, including their thoughts on prenuptial agreements, farting in front of one another and threesomes.
After the segment, Niall revealed that Kimmel left a $25 Dave and Busters gift card in his dressing room.
"Since it's obvious that we're so compatible, Jimmy left this in my dressing room," he said, showing the gift card. Lizzo said she "would love" to go there with Niall, who replied, "We should honestly do that. I'll text you later!"
While it's unclear if they made plans, after the show Lizzo took to Twitter to declare herself a "Horan Dog."
Alongside a clip of Lizzo and Niall taking the compatibility quiz, Lizzo wrote, "Officially a #HORANDOG. There's only 1D I want, honey."