L.E.J, short for Lucie, Élisa and Juliette, sometimes Elijay, are three young female French students and vocalists who condensed numerous top songs from the summer of 2015 into a mashup performance. Their music is based on classical and world music, described by MTV reviewer Joseph Lamour as "eclectic". Their song mashup Summer 2015 had millions of plays on YouTube as of August 2015. According to Seventeen magazine, the three vocalists were best friends from childhood, or BFFs, and have been performing together since 2012. Reviewer Hannah Orenstein described their sound as "pared-down but strong." One of the three vocalists plays the cello and the other plays drums.