Kurumi Mamiya is a Japanese voice actress from Shiga Prefecture who works with the talent agency 81 Produce. She voices Leo in the One Piece anime, produced by Toei Animation, and is also recognized for playing Hamtaro and U-tan on Inai Inai Baa!.
Mamiya provides the Japanese voice of Leo in the One Piece anime, part of the extensive cast Toei Animation has assembled for its adaptation of Eiichiro Oda's long-running manga. The role sits alongside her other well-known character voice work in Japanese animation.
Beyond One Piece, Mamiya is best recognized for voicing the title hamster in Hamtaro and U-tan in the children's series Inai Inai Baa!. She has built her career as a talent under the agency 81 Produce, appearing in a mix of anime and children's programming.

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Kurumi Mamiya provides the Japanese voice of Leo in the One Piece anime, produced by Toei Animation. She works as a talent under the agency 81 Produce.
Mamiya is best recognized for voicing the title hamster in Hamtaro. It stands as one of her most widely known roles alongside her One Piece work.
Beyond Hamtaro and One Piece, Mamiya voices U-tan in the children's series Inai Inai Baa!. Her career mixes anime and children's programming under the agency 81 Produce.
Kurumi Mamiya is represented by 81 Produce. The talent agency backs her roles across both anime and children's programming.
Mamiya is from Shiga Prefecture, Japan. She built her voice acting career there before taking on roles like Leo in One Piece and the title character in Hamtaro.
This content is original writing by Daddy Jim Headquarters based on the One Piece anime series, manga, and official materials. Episode and chapter references are cited where applicable.
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