A doujin music group. Members: 水谷瑠奈/Runa Mizutani (formerly: Sakura Mami) - Lead vocals, lyrics Date of Birth: 22/01/1987 Hometown: Chiba 塚越雄一朗/Yuichiro Tsukagoshi (formerly: ShiroKuma) - Arrangement, sub vocals, instruments Date of Birth: 25/10/1981 Hometown: Nagano The opening theme song for Key Visual Novel: Rewrite, is sung by Runa Mizutani, titled "Philosophyz".