Katy Perry's 'Dark Horse' Shows Off Her 'Genius,' Juicy J Says

'She's really hands on with her music,' Juice tells 'RapFix Live' of working with Katy Perry on 'Dark Horse.'

Juicy J knows how to party, but not every waking moment in the electric rapper's life is a turnt-up twerk-a-thon. Take, for instance, the time Juice worked with Katy Perry on "Dark Horse," an upcoming song from her Prism album.

"I just did something with Katy Perry, man. That song is amazing," Juicy said of the track, which will be released early on September 17 after a fan-voted contest.

Though we haven't heard Juice's verse yet — we've only heard a snippet of the track — a determined Katy appears to have her sights set on a certain lover, and she won't take no for an answer. "So you wanna play with magic/ Boy, you should know whatcha fallin' for," she sings in a breathy tone.

"Dr. Luke called me up and was like, 'Hey man, Katy Perry wants you to do a song with her'," J said of the "Roar" producer.

Juice says that the recording session with Perry went smooth, so when "RapFix Live" host Sway Calloway inquired as to whether or not there was any twerking in between vocal takes, the rapper was very clear in his response.

"No, no, no, no. She's very professional, everything went smooth and she's a great person," he said. "My verse I did on that song, she was singing it. She's really a genius, she was by the mixing board and telling the guy what to take in and take out. She's really hands-on with her music, she knows music."

Though he's been in the industry for over 20 years, Juice is having a resurgence of late, not just in the rap world, but amongst pop artists as well. Justin Timberlake lends his voice to "The Woods" from Juicy's Stay Trippy album and the Three Six Mafia founder has also collaborated with Miley Cyrus on Mike Will Made It's upcoming "23" single and a song of her own that may or may not end up on Bangerz.

"I did a song, I don't know if it's on her album or not, but I did a song with her, it was for her album maybe like five or six months ago," he said. "I ain't seen a tracklisting yet so I don't know if it's on there or not, but the song is super hard. Dr. Luke produced the beat."