WARNING: The following contains spoilers for Season 1 of Shaman King (2021), now streaming on Netflix.
The Shaman King reboot set out to make an anime series that was ultimately more accurate to the manga source material than the original show. In doing so, it glosses over a lot of the old show's filler and adds back in elements that were previously only in the manga. This means that characters are both excised and brought in, depending on their status in the 2001 anime.
Chief among these characters is none other than Manta's parents. Manta's mom and dad were never seen in the old anime, but they were in the manga, explaining their presence in the reboot of Shaman King. Here's a look at the characters' somewhat minor roles and how they're finally adapted in 2021's Shaman King.
Manta's Family in the Previous Versions of Shaman King
In the original Shaman King manga, Manta has not only his parents Mansumi and Keiko, but also a little sister named Mannoko. Mansumi is the stern president of his family's company, and he physically resembles an older, much meaner version of his wide-eyed son. He pushes his son hard to follow in his footsteps, hoping to achieve massive success with the company and literally reach the stars.
Keiko is very similar to her husband, being vain and driven by worldly success. For this reason, she actually tries to forbid Manta from hanging out with the hippie shaman Yoh, seeing him as potentially being a bad reflection on her son and the family's reputation. They also push this mentality onto their computer-savvy daughter, making her the head of the Oyamada Company's finances in order to ride the stock market. Ironically, while Mannoko and Mansumi heavily resemble Manta, with the former essentially just being a gender-bent version of her brother, Keiko has a normal, tall and slender appearance, contrasting with her comparatively super-deformed family.
Manta's Family in the Shaman King Anime
As mentioned, none of Manta's family members show up in the initial Shaman King anime. This, along with Manta eventually becoming a shaman himself in the show, drastically contrasted with the manga. However, they do finally make their minor screen debut in the rebooted Shaman King show.
There, the parents' storylines are essentially the same as in the manga, visiting the somewhat estranged Manta in the hospital after he becomes injured. They become acquainted with Yoh and scold Manta for his association with him, with Manta finally standing up to them to defend his friend. This marks a shift in Manta's personality, as his sudden courage against his family also marks his deepening bond with Yoh.
This change to fidelity to the source material works in the show's favor in terms of making Manta a stronger character, especially since this accuracy to the manga likely means that Manta won't become a shaman as in the 2001 series. It's also a bit ironic given that a lot of the character development and downtime scenes in the original show aren't in this new one, adding to what some fans view as too quick a pace. The consistency with the manga also means, however, that Manta's family likely won't be showing up again in the series.