The actresses have been dating for a year, but only officially went public with their romance in June by sharing a steamy clip of themselves kissing from their movie "Her Smell" on Instagram.
Speaking to Marie Claire about finding love, the star, who has also dated St. Vincent musician Annie Clark, said it was not something either of them planned.
"We weren't looking for it," she told the magazine. "It was really just very authentic and natural."
Cara also spoke about an embarrassing moment in May, when she and the "Pretty Little Liars" star, 29, were pictured carrying a luxury "sex bench" into a shared home in Hollywood, an incident the 27-year-old said was made public, "Definitely not on purpose."
However, she is proud of her sex positivity and tries to be open about her sexual experiences - good and bad.
"I'm not just talking about sex for sex," Cara, who has accused shamed movie mogul Harvey Weinstein of harassment, explained. I'm talking about experience, whether it's abuse or confusion, positive or negative."
The "Suicide Squad" star also opened up about her views on gender during the chat, having come out as gender-fluid in 2018.
"The whole idea of gender is so fixed. I just want to, like, explode it," she told Marie Claire of her identity. "I'm not nonbinary, but I feel as much man as I am woman."
The full interview is available to read in Marie Claire's September 2019 issue.