She was one of the core members of the vocal group Kalafina, which was started by Yuki Kajiura to perform anime television and film theme songs.

[2] In 2007, she was selected to join Kalafina in an audition held by Sony Music Japan, and debuted on their second single "Sprinter" in 2008.

[3] Following the resignation of music composer Yuki Kajiura from Space Craft, Hikaru would later leave the label on October 20, 2018, after her contract expired.

[10] In November 2021, she released her third single "The Sacred Torch", which was used as the opening theme for the anime television series The Faraway Paladin.

[9] In January 2022, she released her fourth single "JUST DO IT", which was used as the opening theme for the anime television series World's End Harem.