Ariana Grande's boyfriend Mac Miller has written a song about the early stages of their relationship.

Mac Miller and Ariana Grande

Mac Miller and Ariana Grande

Mac Miller has penned the track titled 'My Favorite Part' - from his forthcoming album 'The Divine Feminine' - about the 23-year-old beauty, which she also guest vocals on, and has revealed that their romance has been the inspiration for a lot of his music.

Asked if the love song is about Ariana, the 24-year-old rapper - who collaborated with his girlfriend on 2013's 'The Way' - told the USA Today newspaper: "Yeah, but I was writing about certain aspects of our relationship from a long time ago."

Mac also said he would never "out-sing" the 'Dangerous Woman' hitmaker.

He added: "I'm not going to out-sing her in any dimension of the universe; it's not going to happen."

And while Mac isn't shying away from talking about his romance, the 'Bang Bang' singer recently said she felt uncomfortable talking in public about their love life.

She recently confirmed her relationship with rapper via an Instagram picture of the two of them cuddling, but it seems Ariana isn't ready to gush freely about him just yet as she appeared uncomfortable talking about her relationship on 'The Ellen DeGeneres Show' on Wednesday (14.09.16).

Fidgeting in her chair, the star said: "Oh my God, oh God, I don't know, man. This is so crazy. This is so crazy. I've never had the relationship talk on a show before. No pressure."

When pushed for an answer as to whether or not she was in fact dating the 24-year-old musician, the 'Into You' singer simply said: "Oh, yeah."