Mitsuki Yayoi is the stage name of Yayoi Inoue, a former Japanese actress and voice actress born in Tokyo on March 15, 1963. She is a graduate of the drama program at the Toho Gakuen College of Drama and Music. Her career in the entertainment industry began in 1984 when she joined the theater company Gekidan Seinenza, and she later moved to its affiliated agency, Seinenza Film Broadcast, in 2002. Yayoi was active in both live-action television and voice acting for animation until her retirement from the entertainment industry in 2006.

As a voice actress, Yayoi was known for a wide range of roles in anime series, original video animations, and feature films throughout the 1980s, 1990s, and early 2000s. In OVA productions, she voiced Maria Winter in Inferius惑星戦史外伝 Condition Green, Lena in Shamanic Princess, Aira in Green Legend Ran, Maron in Girl from Phantasia, Suzunagi in Ronin Warriors: Message, and Black Ginrei in Gin Rei. She also played Kaede Fujimiya in both the Blue Seed television series and its OVA sequel, Blue Seed Ver. 1.5 [Premium]. In feature-length animated films, her most prominent roles included Riquinni Nonderaiko in the 1987 film Royal Space Force: The Wings of Honnêamise and Chan Agi in the 1988 film Mobile Suit Gundam: Char's Counterattack.

Beyond the roles listed, her voice acting portfolio included parts in television anime such as the role of Nagisa Shiowatari in Urusei Yatsura, Tsukasa in Ranma ½, Jessica in Eat-Man, and a guest role in an episode of Ghost in the Shell: STAND ALONE COMPLEX. She also voiced characters in video games, including the role of Chan Agi in several installments of the SD Gundam G Generation series, with her final performance being in a 2006 game before her retirement.