Movie
Description
Kōji Mihama is a Prism Star affiliated with Edel Rose and a core member of the unit Over the Rainbow, alongside Hiro Hayami and Kazuki Nishina. He is a tall young man with chartreuse eyes and shoulder-length dim gray hair that he ties into a small ponytail, and he wears a dog tag that once belonged to his father, Takeyuki Mihama, as well as a purple Over the Rainbow wristband matching those of his unitmates.

Kōji grew up in a well‑off household. His mother, Natsuko, was the primary earner, while his father, Takeyuki, was a househusband who taught Kōji cooking, baking, and guitar. As a child, Kōji was lively and bright, but the death of his father caused him to become quiet, gloomy, and rarely smiling. During the events leading into the King of Prism series, a falling‑out with Hiro over the song “pride” strained the unit, but that conflict was eventually resolved. Once the rift healed and the troubles in his family were settled, Kōji regained his original energetic and cheerful personality.

Despite his generally kind and soft‑spoken demeanor, Kōji is known to have a quick temper, a trait that Hiro and others sometimes find surprising. He can be unpredictable and mysterious in behavior, but his intentions are always good. He has a deep passion for cooking, a skill he inherited from his father, and in his professional life he hosts a television cooking show while also composing music and performing with the band Cross Road alongside Ito Suzuno and her brother Yu Suzuno.

Kōji is a genius songwriter whose compositions carry a distinctive, sometimes described as devilish, charm. He receives numerous offers from abroad and composes many of the songs for Edel Rose’s female Prism Stars as well as all of Over the Rainbow’s original music. In the King of Prism story, he took on a contract worth twenty billion yen to compose a Hollywood musical epic, partly to help pay off Edel Rose’s debts. Later, he returns as Over the Rainbow reunites, having finished all his songwriting orders.

His relationships are central to his growth: his bond with Hiro and Kazuki is the foundation of Over the Rainbow, and his romantic relationship with fellow musician and Prism Star Ito Suzuno is a steady part of his life. His rivalry and eventual reconciliation with Hiro allowed him to become more open and lively again. Throughout the series, Kōji continues to use his musical genius and personal warmth to support his friends and advance his own career as a Prism Star.