Manta is an intelligent child who carries a book around with him every day. In the Japanese versions, the book is called the Manjien, meaning "Manta's Book on Everything", while the English manga calls the book the "Mantannian Dictionary". "Manjien" comes from Manta's name and the Japanese dictionary "Kōjien". Manta is 13 years old and a 7th grader at Shinra Private Academy; Manta goes to school with Yoh and Anna. He is a Virgo and his blood type is "O."
Manta can see spirits, but cannot use their powers like his best friends Yoh Asakura and Anna Kyōyama can. He is very expressive and a bit panicky. He physically resembles a Koropokkur, and has been mistaken for one of the shy nature spirits on several occasions