Ruka Nemoto is a Japanese female voice actress born on February 10, 1998, in Kanagawa Prefecture, Japan. She is affiliated with the talent agency MILLENNIUM PRO and has been active in the industry since 2013.

Nemoto's career began after she successfully passed an audition for the voice actor training program Spartan MX in 2013. Following this, she and other winners formed the unit Candy Voice, which made its official debut in 2014 with the release of a DVD. Her earliest credited voice role was a minor character in the long-running anime series Detective Conan. In 2015, she landed her first major role as Yū Konoshima in the cross-media project VENUS PROJECT.

Nemoto is perhaps best known for her role as Emperor Penguin in the Kemono Friends multimedia franchise. She first voiced the character in the 2017 television anime Kemono Friends. She later reprised this role for its sequel, Kemono Friends 2, which aired in 2019. Her involvement with the character extended beyond the anime, as she also portrayed Emperor Penguin in the stage play adaptations of the series. In addition to Emperor Penguin, she also voiced the character Okapi in the first season of Kemono Friends.

Her other anime voice roles from this period include parts in series such as The File of Young Kindaichi, The Morose Mononokean, Sansha Sanyou, and Crane Game Girls. Besides voice acting, Nemoto was also active as a member of the idol orchestra group RY's, performing under the name RUKA.