Hiroomi Tosaka, born Tosaka Hiroomi on March 12 1987 in Tokyo, Japan, began his career as a hairstylist before winning Vocal Battle Audition 2 in 2010, which secured his position as a vocalist for Sandaime J Soul Brothers. He debuted with the single "Best Friend's Girl" in November 2010 and contributed to the group’s early chart‑topping releases, earning two Japan Record Awards. Tosaka expanded into acting with Hot Road (2014), receiving the Newcomer of the Year Award at the 38th Japan Academy Film Prize. He launched his solo career in 2017 with the digital single "Wasted Love" and released his first solo album Full Moon (2018), followed by Who Are You? (2020). His singles "Supermoon" (2019) and the Answer… series (2021‑2022) achieved international success, with "You" produced by SUGA of BTS topping iTunes charts in forty‑two countries and reaching Number 3 on the Billboard World Digital Song Sales chart. Tosaka founded CDL Entertainment in 2021, rebranding his solo work as ØMI, and continued to release singles such as "Purple Pill" (2024) and "Feel Gold" (2024). His second EP, THE FUSION, was released in January 28, 2026 and reached number one on the oricon chart.