Manta has short sandy-brown hair and large eyes. Throughout the manga he is usually shown wearing his school uniform - green pants, running shoes, white dress shirt and tie. His casual outfit consists of white shorts, and a blue hoodie with white angel wings on the back and a halo on the hood. And he usually has his laptop with him.
He is by far the shortest of the group, measuring in at 80 cm (2 feet, 7 inches). Because of his small stature, he is often mistaken for a Koropokkuru (known as "Minutians" in the English Anime).
Manta is very intelligent and studious, attending cram school and constantly carrying around a large book. 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" is a portmanteau of Manta's name and the Japanese dictionary "Kōjien".
He is very expressive, and he often panics or gets over-excited.
Powers & Abilities
Manta can see spirits, but is not trained as a shaman so he cannot use their powers like his best friends Yoh Asakura and Anna Kyoyama can.
Coming to Tokyo
Manta first appears trying to head home after cram school. He goes through the cemetery as a shortcut and runs into Asakura Yoh, who asks him to stargaze with everyone. This confuses Manta, since Yoh is alone, but he reveals "everyone" to be the ghosts of the cemetery. Manta panics and flees.
The next day, Manta tries telling his classmates about the incident, but they don't believe him. Yoh is introduced as a transfer student and Manta freaks out after Yoh explains to him that he is a shaman. Later that night Manta returns to the cemetery, wondering if Yoh is watching the stars again and runs into Ryunosuke Umemiya, nicknamed "Wooden Sword" Ryu and his gang, who beat him up.
Manta, again, tries explaining the situation to his classmates, who once again laugh at him. Yoh reveals that he was told what happened by the ghosts of the cemetery, and drags Manta back there to face Ryu. Manta panics a little and asks Yoh why he is doing this to which Yoh says that is because Manta is his friend. They confront Ryu and his gang, and Amidamaru appears, wanting to get revenge on Ryu for breaking his tombstone earlier. Yoh performs Hyoui Gattai and they easily defeat Ryu and sever the end of his pompadour.
Later on Yoh asks Amidamaru, bluntly, to be his guardian ghost, but Amidamaru declines, saying he is waiting for someone. Yoh and Manta go to the local museum to see Harusame, Amidamaru's sword, and meet Mosuke, who reveals himself to be a blacksmith and friend of Amidamaru. He tells the two the story of his and Amidamaru's past and why he is called a demon. Yoh performs Hyoui-Gattai with Mosuke and reforges Harusame after bringing the new sword back to Amidamaru he agrees to become Yoh's guardian ghost.
Days later Yoh is worried about a bilboard that fell on him, while Manta wants him to worry about his Kendo test. Yoh however introduces other ghosts who helps Yoh at school. Manta calls him a coward and runs away. On his way the same billboard from fell again on Manta, though he evaded the billboard with the help of Amidamaru who then reveals the earthbound spirit that posseses the billboard. After Amidamaru protects him from the ghost again Yoh arrives telling everyone that the earthbound ghost is Kanta who died before he could finish the billboard. The earthbound spirit changes to his human form and Manta watches Yoh through finishing the billboard.
Shaman Fights First Round
Since he is not a shaman, Manta does not get involved in the fights, but he is always there with Yoh to watch each round. However, upon meeting Faust for the first time before his fight with Yoh, Manta became victim to Faust's medical "research", spurring Yoh's anger and ultimately causing him to lose that round.
Traveling through America
Shaman Fights Second Round
Invading the Plants
During this segment of the Shaman Tournament, Manta stays behind on the island while the finalists traveled to the Lost Continent, Mu. Manta expresses melancholy for the fact that he could no longer support the others. After a conversation with Anna, over the actions of the Five Warriors going after Hao, he receives the mental image of Hao being a ‘princess’ under ‘evil influences’. He later dreams of this, and becomes increasingly confused about Hao’s true characterization. Manta also becomes aware that the others are still trying to save Hao, knowing that even if he is defeated the cycle won’t end. And as Manta laments over the fact that he is of no help, Anna arrives and explains he is late as everyone is prepared to travel to Mu.
Funbari no Uta
He has grown 1 cm taller and is in a rich company making lots of money. He is also a College student and he investigates the benefits of mixing shamanism and business.
In the manga and Japanese anime, Manta has an assistant, Tamurazaki. In the English anime, Tamurazaki (who turns out to be Mansumi's lapdog and guns down at least one of Hao's followers) is "Uncle Jerry" and is Morty's uncle. In the English anime, Morty is a fan of ghost stories and the book he carries around is a ghost story book.
In the anime, Manta is shown to posses some Shamanic ability by oversouling with Mosuke, using his laptop as the medium.
- The name Morty is a pun of the Latin prefix for "death" (with which words begin with mort-, mor-, or mori-) and the word mortal.
- Manta's family name means "small mountain field".
- Manta is the first character to be officially introduced in both manga and anime.
- Manta gets the first and last line in the manga.