Jackie is a young idol with two old friends. The first is Yeye, also known as Moon, and the second is Kei, whose full name is Kei Sora—Jackie’s favorite. The band name JKY comes from the first letters of their names: Jackie, Kei, and Yeye. Jackie really wanted Kei to join the band, but Kei declined, which made Jackie a little upset. He didn’t push Kei, though, and instead formed another band called *Moon & Star*.