The 28-year-old singer has told The New York Times that her hotly-anticipated collaboration with the 'positions' hitmaker was a last-minute addition to her LP.
The confirmation comes after Ariana posted her vocals on her Instagram Story and captioned the post: "backgrounds on a song for a friend (sic)"
Demi then excited fans further when she shared Ariana's post and added sneaky-eye emojis.
Elsewhere in the interview, Demi teased two tracks on the record, firstly, 'Melon Cake', which is about taking back control and is named after the watermelon and fat-free cream she would be given instead of a birthday cake.
Demi then teased the song 'California Sober', which is described as "strummy mid-tempo", and reflects where she is in her sobriety.
She admitted: “I haven’t been by-the-book sober since the summer of 2019. I realised if I don’t allow myself some wiggle room, I go to the hard [expletive]. And that will be the death of me.”
The follow-up to 2017's 'Tell Me You Love Me' - which is released on April 2 - is set to act as a companion to her upcoming Michael D. Ratner-helmed documentary series, 'Demi Lovato: Dancing with the Devil', which explores aspects that led to the singer's nearly fatal overdose in 2018, and her "awakenings in the aftermath".
During a recent Clubhouse live-stream, Demi said: “It really does follow the course of my life and the path it’s taken over the past few years."
The 'Sorry Not Sorry' singer also teased that she has recorded collaborations with “three different, incredible women.”
The "deeply personal" LP, which boasts 19 songs and three bonus tracks, is executive produced by Demi and her manager, Scooter Braun.
In a statement, the 'Sober' singer said of her four-part documentary series, which will be available on YouTube starting March 23: "It's been two years since I came face-to-face with the darkest point in my life, and now I'm ready to share my story with the world. For the first time, you'll be able to see my chronicle of struggle and ongoing healing from my point of view. I'm grateful that I was able to take this journey to face my past head-on and finally share it with the world."
The series will also include career highlights such as her landmark performance of the National Anthem at 2020’s Super Bowl.
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