Kō Ōsaki is a character from the anime series Shōnen Hollywood - Holly Stage for 49 and its sequel, Holly Stage for 50. He was a member of the original Shōnen Hollywood, the legendary idol group that performed at the Hollywood Tokyo theater fifteen years before the events of the main story. He joined the group during its founding phase, becoming part of the initial lineup that would go on to capture the hearts of many fans.

In terms of personality, Kō Ōsaki is remembered as a cheerful individual who laughed easily at small matters. During his time with Shōnen Hollywood, he brought a lighthearted and warm presence to the group. His primary motivation was his love for singing; he wanted to continue performing and pursuing music beyond his time with the group. This dream eventually came true.

After Shōnen Hollywood disbanded, Kō Ōsaki transitioned to a solo music career. He continued to work in the entertainment industry, primarily within the music sector. His post-group life reflects a dedication to his craft and a desire to keep his artistic ambitions alive even after the original group dissolved.

Within the narrative of the anime, Kō Ōsaki appears as a supporting character. He represents a link to the past, illustrating the legacy of the original Shōnen Hollywood and the different paths its members took after the group ended. His story provides context for the current generation of idols training at Hollywood Tokyo, showing that dreams can evolve but remain attainable.

Kō Ōsaki is also associated with the song Endless Stripe, which serves as a notable piece of his musical output. His overall journey from a founding member of Shōnen Hollywood to a solo artist highlights a career built on persistence and a genuine passion for performance.