(One of the Three Universal Music Artists. The Immortal Sisters are a girl group of five Sisters which are all Immortal. The oldest is Muki and she is the main singer. Next is Miku and Miki who do backup vocals. Then its the two younger twins, Meku and Maka that play instruments. All background music is done by their big brother, Muku. The Immortal Sisters specialize in looking cute but playing dark, morbid and gloomy music as well as dark synth and collaborations) Muki: We Are Immortal Sisters.