Characters

1. Mukaido Manaka

Manaka is a young girl, with long brown hair and light blue eyes. She is often seen in the white and blue uniform of her old school from beneath the sea, which was closed down.

At the beginning of part 1, Manaka is a quiet, shy, crybaby who needed other people to fight her battles. But after some encourage from Chisaki and Tsumugu, she began to grow braver and while the anime progressed, so did she. By the end of part 1 (episodes 1-13) Manaka has become louder, bubbly, kind and hardly ever cries. She sees goodness in everyone and is the most selfless character as she took Akari's place to that Akari's family would be sad.

 "Everyone is someone precious to someone! Please don't forcefully rip apart those who love each other!"Manaka to the sea god.

2. Sakishima Hikari 

Hikari has the trademark blue eyes of the sea-folk and red-brown hair, he is regularly seen in the blue and white uniform of his original school from beneath the waves which was closed down. And in part two, he is in a navy blue hoodie and jean shorts.

Hikari is at the very beginning exuberant, brash, inattentive, and heedless to formality or social standings, but this changes during the anime. He develops into a calm, wise and kind person. He generally holds a deep scar on his heart after his mother dies and finds it hard to let people go as he does not what to let Manaka go. In part 2, he becomes a little depressed as he is over come with worry for Manaka, thee woman he is in love with. He tends to over thinks things at time and ignores little things. Hikari tends to act on his feelings for Manaka a lot, during the anime he had acted on them almost five times and has a strong impact on everyone he meets. He knows when he goes to far and admits to it

"At the time, no matter how far I reach to you, it didn't get to you. But never again. I'm never letting go." Hikari talking about Manaka after saving her

3. Hiradaira Chisaki

Chisaki is a tall enough girl with gray-lavender hair and slanting blue eyes. She is often seen in her blue and white uniform from her old school that closed down.

Chisaki is kind, friendly and very caring. She takes on a motherly role on their group, being a bit more mature than Manaka and Hikari, which is a constant source of entertainment to Kaname. She can show signs of jealousy and has the occasional angry outburst, for which she always feels guilty after. She wants her friendship with Hikari, Manaka and Kaname to prevail no matter what, and she is afraid of the changes they start to experiment after going to the surface.

4. Isaki Kaname

Kaname has long (for a boy's standard) beige hair. He has blue eyes, and is of an average height. 

Kaname is an easy-going boy, and usually has a friendly smile on his face. He's a typical bishounen, and he cares greatly for his friends. He always gives Chisaki his support and encourages her regarding her feelings for Hikari. Kaname always looks out for her but it's not clear if he holds special feelings for her or not. Until the 10th episode where he confesses his feeling for her, saying that he has loved her for a long time. While he doesn't want to press her for an answer at first, he does end up telling her his feelings but she never seems to respond. Even after He comes up from the surface of the water 5 years after the Ofuneki. He seems to get jealous whenever Chisaki and Tsumugu are together.

"I'm doing the best I can too."

5. Kihara Tsumugu

Tsumugu is one of the main characters in the series. He is a human with the roots in both the land and the sea. His grandfather (who he lives with and fishes with) was allegedly one of the sea-folk who came to live on land, which may be the reason why his eyes are such an unusual colour. He is a quiet, thoughtful boy, who is the first to treat the children from the sea kindly when they arrive at his school. 

He has messy, grayish black hair that goes down to his shoulders. He also has light-dark lavender eyes. He is often seen in his white and gray school uniform, with a brown vest peeking from inside and brown trousers, and normal footwear. In part 2, Tsumugu wears a dark red sweater, black shirt underneath with a pair of skinny jeans.

Tsumugu is quiet, well spoken and thoughtful boy. He seems to spend a lot of time by himself or with his grandfather. He has an avid curiosity about the sea-village and what goes on down there, so much so he helps with the Ofunehiki preparations, despite Hikari's negativity towards him at first. He also gives good advice, and possibly has feelings for them.