"You know, we just, we like what we like," Brody says in the clip.
While speaking to Kaitlynn and Brody via a Facetime call, Kaitlynn's pal, Liz, brings up the subject as Stephanie Pratt apparently had been asking questions.
"She's just, like, asking about your relationship," Kaitlynn's friend says of Stephanie. "She's like, 'I don't know. Isn't there someone else, like, involved?'"
"What does she mean by that?" Kaitlynn asks and Liz responds, "She thinks you guys are like in this, like, polyamorous relationship."
Brody immediately speaks up. "That's none of her business," he says. "You know, we just, we like what we like."
Kaitlynn then further weighs in the situation in a confessional, shedding light on the beginning of their relationship.
"When Brody and I first were together, we were young, we were crazy, we were, like, you know, basically just trying to have the time of our lives," she recalls. "So we did a lot of things in our relationship that, you know, I certainly wouldn't say I regret, but the level of gossip that I feel happens in the group -- it just makes me angry.”
The couple announced their split earlier this month.
"Brody Jenner and Kaitlynn Carter have decided to amicably separate,” rep Scott Newman said in a statement at the time. "They love and respect one another, and know that this is the best decision for their relationship moving forward."
It was also later revealed the couple were never legally married, despite having a wedding ceremony in Indonesia in June 2018.
A few weeks later, Kaitlynn was photographed kissing Miley Cyrus while on a girls trip to Italy.
At first, Brody seemed the mock his ex's behavior after their split, however, he then took to Instagram to "set the story straight" about where the two stand now.
"There is far too much negativity being directed at someone who I love and care about very much," he wrote. "I feel the need to set the story straight. Kaitlynn and I have been best friends for 6 years, and we continue to be. We, like many others before us and many after us, grew in different directions over those same 6 years."
"Kaitlynn is a wonderful person, beautiful and fun to be with, always a positive force in my life," he continued. "We decided the best move for both of us was to keep our love for each other strong but move forward separately with our lives. I respect Kaitlynn and care deeply about her. She deserves to be able to move forward in her life with respect and happiness."
In the comments, Kaitlynn was one of the first to respond, leaving a heart emoji.
"The Hills: New Beginnings" airs on Monday nights at 10 p.m. ET. on MTV.
Got a story or a tip for us? Email TooFab editors at firstname.lastname@example.org.