Youji Asano is a professional alias used by the Japanese voice actor Koji Yusa, primarily for work in adult-oriented anime and games. This alias distinguishes his performances in these genres from his mainstream roles.

Koji Yusa was born on August 12, 1968, in Kyoto, Japan. He began his voice acting career in 1993 after training at the Katsuta Voice Actor's Academy, debuting in the anime The Brave of Gold Goldran. He initially worked for the agency Office Kaoru but later became a freelancer.

Under the alias Youji Asano, he has voiced characters in numerous adult OVA series, many of which are based on visual novels. The specific roles mentioned are confirmed as part of his filmography under this name. In the 2005 OVA The Hills Have Size, he voiced the role of Ryoji Matsubara. In the 2002 OVA series Momiji, he played the character Kazuto Mikado. He is credited as Tatsuya Katori in the series The Immorals, which is also known as 女系家族 〜淫谋〜. For the 2005 OVA Insatiable, he provided the voice for Shunji, who is also known as the Masked Gentleman. His work also includes the role of Shinji Touasaikuhara in the Tony's Heroine Series installment Kanojo wa Hanayome Kōhosei? Cinderella Collection, though the character name in available records is often listed as Rindo Naoto for the related series 燐月.

Beyond his adult-oriented work as Youji Asano, Koji Yusa has a distinguished career in mainstream anime and video games. He is well-known for voicing Gin Ichimaru in Bleach, Shadow the Hedgehog in the Sonic the Hedgehog series, and Urataros in Kamen Rider Den-O. For his role in Kamen Rider Den-O, he was a recipient of the Synergy Award at the 2nd Seiyu Awards. His voice is often described as smooth and soft, frequently cast for bishōnen or affable adult male characters.