|Name: Kaito Domoto (堂本 海斗 Dōmoto Kaito)|
|Birthday: November 21|
|Birthplace: Panthalassa Kingdom|
|Species/Race: Panthalassa Clan|
|Hair Color: Ginger|
|Eye Color: Brown|
|Height: 172 cm (5'8")|
|Star Sign: Scorpio|
|Profession: Surfer, Student|
|Favorite Subject: Gym, Math|
|Least Favorite Subject: Social Studies|
|Favorite Color: Blue|
|Favorite Food: Stew|
|Favorite Type of Girls: Low Maintenance Girls|
|Family: Gaito (brother), Makoto (cousin)||Best Friend: Unknown|
|Love Interest: Lucia Nanami|
|Voice Actor: Daisuke Kishio|
|Position in the Series: Main Character|
Kaito (堂本 海斗 Dōmoto Kaito) is in love with Lucia and is the twin brother of Gaito. He is an orphan because his parents died in a ship when a big storm (caused by Sara when her pearl is out of control) and the ship is rolled by the gigantic waves. These aren't his real parents, as he found out later. He was a child of the Phanthalessa.
He is the twin brother of Gaito. This is because the Phanthalessa indulged their descendant's power into the two twin boys which, when joined, allows power to destroy the world. This is why Aqua Regina separated Gaito and Kaito. He washed up to shore wrapped in seaweed after a storm and a couple who were musicians found him. From there they raised him. While Kaito and his parents were on a cruise Sara was angered by Taro abandoning her and she created a big wave that shipwrecked the cruise ship and killed both of Kaito's parents. Fortunately, Lucia saved Kaito and brought him back to shore. He continued to be unconscious so Luchia used her pearl to save him. And he wound up raising himself.
Kaito is very interested in surfing, and is a very easygoing person. He is shown to be popular with girls and can be quite flirtatious, even perverted to an extent, as he comments on Lucia's outfit that her clothes are cute, but he prefers "more racey outfits."
He is completely oblivious to the fact that Lucia is the mermaid that saved him as a child. Despite this, he had several times where he questioned if Lucia could be that mermaid and compared her human and mermaid forms throughout the series.
His hair is orange-brown a little red and spiky and he has brown eyes. As pointed out, he resembles his brother Gaito. He wears a variety of different clothes on land such as a white jacket and black turtle neck or a red jacket and a white shirt. While surfing he wears a red, black, and slightly yellow wet suit. In water he wears a blue, red, and yellow outfit with a whiteish cape. His school uniform looks like any other male uniform of his school with a white button down shirt and blue pants.
See: Kaito Domoto/Gallery
- Chinese: Lin Guzhen
- French: Emmanuel Deknoinck.
- Greek: Yiorwos Mataragas (Γιώργος Ματαράγκας)
- Italian: Simone D'Andrea
- Japanese: Daisuke Kishio
- Korean: Byeon heyon woo
- Portuguese: Sérgio Calvinho
- Serbian: Milan Antonić (Милан Антонић)
- Spanish: Alvaro Navarro