Demi Lovato Sang Ariana Grande's "Bang Bang" Verse With Jessie J, Crowd Collectively Lost Their Sh*t
4 December 2014, 16:51 | Updated: 8 May 2017, 17:09

It might get loud.
At Jesse J's concert in San Jose, California, a surprise guest in the form of Demi Lovato joined her on stage, and they sang 'Bang Bang' together.
And people really, really liked it.