Demi Lovato sings her heart out in the official visual for her brand-new single "Nightingale" dedicated to her loyal fans, Lovatics. The powerful ballad was written by the 22-year-old singer-songwriter together with Anne Preven, Matt Radosevich and Felicia Barton. The song is an ode to Trenton Cole Stout, who was one of Demi’s best friends that hung himself. She considers him her guardian angel. The track was produced by Matt Rad and Reece Pearson. It serves as the fifth single from Demi Lovato's upcoming fourth studio album 'DEMI', scheduled to be released by Hollywood Records on January 13, 2015. The black-and-white music video was directed by Black Coffee. The short clip shows highlights from Demi's tour and features live concert footage. Demi Lovato's boyfriend makes a cameo appearance as they share a passionate kiss.