Krewella formed in 2007 and consisted of sisters Jahan and Yasmine Yousaf, whose father is of Pakistani descent, along with producer Kris Trindl. The three met as students at Glenbrook North High School. Their music is a blend of self-produced electro house and dubstep, with influences of many other EDM styles. All three members of the band have "6-8-10" tattoos to commemorate June 8, 2010, the day when the three agreed to give up their careers, schooling, and any other intentions for their lives, to dedicate all of their time to the band's joint music career. In December 2011 Monstercat signed Krewella; "Killin' It" was Krewella's first original song released by a label. Monstercat promoted Krewella with social media campaigns and partnered with EDM YouTube promotional channels for a larger platform. In June 2012, Krewella released their EP Play Hard. The second single, "Alive" peaked at number three on the US Dance/Mix Show Airplay chart and it also placed on the US Billboard Hot 100.