Image Source: Getty / Kevin Mazur/One Love Manchester [1]

After touching down in the UK [2] on Friday, Ariana Grande [3] returned to the stage for her star-studded One Love Manchester concert [4] on Sunday. The 23-year-old singer was joined by pal Miley Cyrus [5], Katy Perry [6], and Justin Bieber, and she teamed up with boyfriend Mac Miller [7] for a surprise duet with undeniable chemistry and adorable dancing. "Tonight is all about love," Ariana told the audience. She wore a sweatshirt that read "One Love Manchester" and a diamond sparkler on her ring finger.

Image Source: Getty / Mike Coppola/MTV1617 [8]

While Ariana and Mac have yet to confirm any engagement rumors, it's also worth noting that Ariana has been wearing the sparkler on her Dangerous Woman tour since February. Ariana and Mac first sparked dating rumors [9] when they were caught sharing a kiss during a romantic sushi date back in August 2016.

Image Source: Getty / Kevin Mazur/One Love Manchester [10]