Ariana Grande, Elizabeth Gillies Accidentally Post Video of Kiss to Instagram

Ariana Grande and her "Victorious" co-star and friend Elizabeth Gillies accidentally posted a video of themselves kissing to Instagram.

The 22-year-old "Break Free" singer locked lips with the "Sex&Drugs&Rock&Roll" actress, and the video found its way onto social media on Monday, according to People.

As the pair prepares to smooch in the video, Gillies says, "It has to be pretty though."

Gillies told People in June how she first bonded and became close with Grande after appearing in the 2008 musical "13."

"She's like blood to me, she's like my sister. So unless we have a massive falling out, nothing will be happening there," Gillies said. "We lived together, I've known her since what feels like the beginning of time."

Grande and Gillies reunited for the Nickelodeon show "Victorious," which aired on the channel from 2010 to 2013. Both girls were able to showcase their vocal skills on the show, which followed young aspiring students in a Hollywood arts high school. The show, created by Dan Schneider, also included cast members Victoria Justice, Leon Thomas III, Matt Bennett, Avan Jogia and Daniella Monet.

Now that Gillies is featured on a much more risqué show on FX, she says she is able to tap into her true and more mature self.

"Even when I was on Nickelodeon, I talked and had the sense of humor of someone much older than me, so it's fun for me to kind of be myself more on this," Gillies said. "Not that I wasn't then -- I was younger! I did 'Victorious' when I was younger, so I think it's just a natural progression."

"Sex&Drugs&Rock&Roll," which also stars Denis Leary, John Corbett, Robert Kelly, John Ales and Elaine Hendrix, airs Thursdays at 10 p.m. ET on FX.