Japanese artist whose identity was initially kept anonymous ("神出鬼没・正体不明のアーティスト" — an elusive, unidentified artist). Signed to Sony Music (BEAT SEEKER MUSIC). Made his major debut in 2020 with the single "Yume?" (夢?), the ending theme for Taisou Zamurai. In December 2025, it was revealed that he is the son of singer Mori Shin'ichi and the younger brother of Taka (ONE OK ROCK) and Hiro (MY FIRST STORY). He continues to perform under the stage name "Hatena."