Yūsuke Ōnuki is a Japanese performer whose primary career is as a dancer and stage actor, but who is also known to anime audiences for his voice role as Daisuke Kanbe in the series The Millionaire Detective - Balance: UNLIMITED. He was born in Kanagawa Prefecture on August 31, 1988, and is affiliated with the talent agency Horipro. Before entering the entertainment industry, he trained in various dance styles from the age of seven, including ballet, jazz, and hip hop, and began working as a professional dancer at seventeen.

Ōnuki's performance career began on the stage. In 2011, he was cast in the musical Romeo and Juliet, which served as his debut. He has since built an extensive career in theatre, appearing in numerous musicals and stage productions, such as the Japanese version of Mary Poppins, a stage adaptation of Fist of the North Star where he played the lead role of Kenshiro, and the play Harry Potter and the Cursed Child, in which he portrayed Harry Potter. His work is not limited to stage; he has also appeared in live-action television dramas and films. Notable credits include the drama series The Millionaire Detective – Balance: UNLIMITED's live-action counterpart, The Lupin Family, and the historical drama What Did You Eat Yesterday?.

Ōnuki's entry into voice acting occurred in 2020. He was cast as the co-leading character Daisuke Kanbe in the television anime The Millionaire Detective - Balance: UNLIMITED, marking his debut as a voice actor. This role stands as his most prominent and defining work in the field of animation. That same year, he also contributed his voice to the Japanese dub of the film Cats, providing the voice for the character Skimbleshanks. Outside of these two credits, his filmography as a voice actor is currently limited, with no other major anime roles or recurring collaborations with specific directors or studios recorded in available sources. His work as a voice actor remains a distinct but minor facet of a broader career centered on physical performance.