Yoshiyuki Hirai is a Japanese voice actor and comedian, born on March 12, 1973, in Hirakata, Osaka Prefecture, Japan. He is best known as the boke half of the comedy duo America Zarigani, which he formed with Tetsuya Yanagihara in 1994. Beyond his work in comedy, Hirai has built a substantial career as a voice actor in anime and video games, leveraging his deep personal interest in anime, manga, and gaming.

One of his notable early voice roles is Bongo in the anime series Bomberman Jetters. He has also portrayed Santo in Natsume Yujincho, Geki Honba in Inazuma Eleven, and a character named Taira Yoshiyuki in The Prince of Tennis. On film, he voiced Zaku in Arashi no Yoru ni. His voice acting extends to the game industry, where he has contributed to major franchises such as the Professor Layton series and the Ni no Kuni series, playing the character Smiley in the latter. He also provided the voice for Golem Bomber in the Super Bomberman R games. In the Monster Hunter series, he is recognized for inspiring the AmeZari Armor set in Monster Hunter 2nd G.

Beyond performing, Hirai has shown creative ambition as a producer. He conceived, composed, and designed the cell phone anime series Akachan (56), in which he also voiced a role. His work in the virtual space includes stepping into the world of VTubing, where he established his own VTuber agency named Enishin and has overseen the production of various virtual talents.