19 (Chronologically after time skip)
|Birthday||January 28 (Aquarius)|
|Eye colour||Ocean aqua-blue|
|Hair colour||Hazel brown|
|Status||Alive | Student|
|School||Nami Elementary (formerly)|
Nami Middle School (formerly)
Mihama Middle School
|Family||Tomoru Sakishima (Father)|
Hokage Sakishima (Mother - Deceased)
Akari Sakishima (Older sister)
Itaru Shiodome (Brother-in-law)
Miuna Shiodome (Step-niece)
Akira Shiodome (Nephew)
|Friends/Allies||Manaka Mukaido (Childhood friend)|
Chisaki Hiradaira (Childhood friend)
Kaname Isaki (Childhood friend)
Tsumugu Kihara (Close friend)
Sayu Hisanuma (Junior classmate)
Egawa Takeshi (Classmate)
Sayama Shun (Classmate)
Sensei (Close acquaintance)
Isamu Kihara (Close acquaintance)
|Relationships||Manaka Mukaido (Girlfriend)|
|Manga Debut||Volume 1, Chapter 1|
|Anime Debut||Episode 1: "In Between the Sea and the Land"|
|Japanese Voice||Natsuki Hanae|
|English Voice||Max Mittelman|
Hikari Sakishima (
Hikari is considered as a handsome young man with brown hair that is swept to the right side and deep blue eyes which is the color of the ocean (like all people from the sea).
Hikari is regularly seen in the blue and white uniform of his original school, Nami Junior High, from beneath the sea which was closed down.
After his hibernation, he is seen wearing his school's uniform at school and casually wears a blue hoodie and a pair of shorts. As well as his new Mihama Middle School uniform.
At first, Hikari looked down upon people from the surface, viewing them as inferiors who threw away what the sea king gave them in exchange for their own greed. As seen with Manaka Mukaido, he has a great deal of pride for his life in the sea. He is short-tempered, aggressive, energetic, and impulsive, but fiercely loyal. He's also very determined when it comes to Manaka.
However, Hikari soon matures and comes to terms with people from above the sea, soon acknowledging that they aren't different and starts to wish they could work together.
When he was young, Hikari's mother passed away. Distraught by this loss, Hikari openly wept at her to wake up while being comforted by his older sister Akari Sakishima. Their father has been taking care of them and change. Leaving to go to school with Chisaki Hiradaira and Kaname Isaki, Hikari waits at the exit of the ocean for Manaka Mukaido but she does not show up. Waiting longer, he is surprised to find that she had been caught by the net of a fishing trawler.
At school, Hikari takes part in introductions but quickly gets irritated as the surface dwellers make fun of him and his friends for being from the sea. Arguing and insulting them back, Hikari attempts to get Manaka to do so as well but is unable to as Chisaki stops him once again. During P.E, Manaka races Tsumugu Kihara, whose grandfather fished up Manaka that morning. While running, Hikari loses his balance and falls onto Tsumugu, taking both of them down.
Later that day, Hikari meets Akari on his way home and discusses her recent vandal problem. Upon returning underwater, Hikari is spoken to by a mens club who are angry with the surface dwellers' recent actions against them. As he recalls the history of people and their origins, he takes his leave and meets with Manaka. Visiting Lord Uroko at the shrine, Hikari witnesses him approach Manaka, causing her to cry and run away and he to curse her as a result.
The next morning, Hikari and his friends head to Manaka's house to pick her up but find that she is refusing to leave. Heading to her bedroom alone, Hikari asks her what the problem is and finds that her kneecap has become a fish head. Knowing that this was the curse Lord Uroko used, Hikari gets angry but quickly sets it aside. As she continues to refuse to go, hoping nobody will see it, Hikari eventually convinces her to go by covering the head up.
However, Hikari comes to find out that Manaka ran away from school and goes out to look for her with Chisaki and Kaname. Despite their efforts, they are unable to locate her and forced to return to the water due to their skin cracking. However, Hikari later resumes the search and finds Manaka alongside Tsumugu, whom he attacks. After being pulled off by Manaka, Hikari laments her apparent closeness with Tsumugu as the two of them return home.
Manaka is one of Hikari's childhood friends. Hikari has always had feelings for Manaka and he would do anything to make her happy, which is the reason why he calms her down a lot in the series. He gets very jealous when Manaka is around Tsumugu, but after he learned about the relationship of the land and sea people, he decides to support Manaka and her feelings for Tsumugu. While reliving some of their memories from their old school, Kaname asks Hikari about his feelings for Manaka. Hikari finally confesses his true feelings to her. This shocks and saddens her as she yells that she doesn't know what love is and Manaka runs away and Hikari chases after her. After a while, Manaka returns home and meets with Hikari. He reaffirms his feelings for her and she says she has something to tell him after the Ofunehiki. During the ceremony, he, along with Manaka and Kaname, all fall in hibernation, while Chisaki avoids it.
After the timeskip, he searches for Manaka with Kaname's and Miuna's help and successfully finds Manaka in an Ojoshi-sama graveyard. Hikari promises he'll never let go of her after she wakes up because he doesn't want what happened at the Ofunehiki to happen again. But, after she wakes up a week after they find her, he finds something fishy about her. When Hikari asks Manaka to tell him the thing she wanted to tell him after the Ofunehiki, he realizes that she had forgotten all her memories of love and now where her love is a big hole screaming it's lonely. Thus she is never able to confess her feelings for Hikari after the Ofunehiki, and never being able to love him again. But, Hikari believes that she was in love with Tsumugu and not him seeing that she rejected him after he confessed his feeling for her. Even though he thinks that, Hikari thinks more about Manaka more than his own feelings about her. He wants her to remember what it feels to like someone and have happiness once again.
After they decide to do the Ofunehiki again to gain Manaka's feelings back, he tells her she will gain back her memories of love back no matter what. It is soon revealed that Manaka is in love with Hikari and that their love wasn't one-sided. Manaka tells Tsumugu that Hikari is like the sea, always protecting her. At the final scene the two walk on the beach, she asks him if he remembers their talk from five years before when she said she would tell him something after the Ofunehiki. He responds that he already knows what she was going to say. Hikari and Manaka watch the sea together, now certain of their feelings for each other.
Chisaki is one of Hikari's childhood friends. The two were always together with Kaname and Manaka when they were in junior high. Chisaki is secretly in love with Hikari, but Hikari doesn't have the same feelings because he is already in love with Manaka, and her feelings for him is unrequited. Later, Chisaki decides to confess her feelings for Hikari, but after learning that Hikari is in love with Manaka, she becomes upset and holds back admitting her feelings, not because she was afraid of being rejected, but was afraid that their relationship would change, and eventually realizes that Manaka means a lot to him and tells him to go after her. Despite her confession, Hikari remains oblivious to fact that she's in love with him, and only replies to her that he too was afraid of changing and this is never brought up again.
After the time skip, she has gotten over him, but she doesn't want to change so she tries to make herself love him again. She made sure that she wouldn't forget that she was in love with him. After finding out that Tsumugu is in love with her, she turns him down and Kaname encourages her to be honest with her feelings, but she claims that doing so would betray any feelings she had for Hikari, despite knowing he still loves Manaka. Soon, she finds out that Manaka is in love with Hikari, which allows her to move on from her unrequited feelings for Hikari, because she knew they were meant to be together and where Chisaki realizes she is actually in love with Tsumugu.
Kaname is one of Hikari's childhood friends and best friend. The two were always seen hanging out together with Chisaki and Manaka when they were in junior high.
At first, Hikari hated Tsumugu because he was the person that Manaka seemed to have feelings for. But after he realized that Tsumugu is a nice guy, he decides to support Manaka and starts to be friends with him. Tsumugu also loves Manaka's fish that was on her knee. That's why he would always ask if it was okay. He also starts to develop feelings for Chisaki. While Hikari tries to get Kihara to fall in love with Manaka, Kihara tells Hikari that he actually loves Chisaki. Chisaki overheard what he said and ran into the ocean. Kihara ran after her while he got ena because of the ena he got from his dad.
Miuna is Hikari's step-niece. Even though Miuna is Hikari's niece, Miuna has romantic feelings for Hikari. However, Hikari only thinks that Miuna's feelings for him are because they are family. Miuna cannot act upon her feelings because of the same reason and doesn't want Hikari to ever know that she is in love with him. She knows she'll never change Hikari's heart, because he is in love with Manaka and tries to forget it with pain by forcing him to admit several times that he loves Manaka.
She becomes the sacrifice of the Ofunehiki in order to save Manaka and remembers that she is in love with Hikari as she falls asleep. When he learns of her true feelings for him, he becomes conflicted and blames himself for not realizing Miuna's feelings for him sooner and that he was hurting her when she forced him to admit his love for Manaka, but questions why she would have any feelings for him. During his continued attempts to save Miuna, he offers his own feelings to the sea god in place of Miuna to experience what Manaka was saved from that would cause immense pain for him even though he is not in love with her.
After the second Ofunehiki, Miuna finally moves past her unrequited feelings for Hikari, looking forward to the future where she believes new feelings will be born, while nothing changes for Hikari, as he and Manaka acknowledge each other's feelings.
Akari is Hikari's older sister. When they were little, Hikari used to called Akari "Onee-chan", but after the death of their mother, Hikari started to called Akari by her name because when their mother died, Akari did not cry. But after he supported her loved for Itaru, Hikari started to call her "Onee-chan" again.
Tomoru is Hikari's father. Hikari hated his father because Tomoru declined to have the Ofunehiki and didn't support Akari's love for Itaru. However, their relationship is mended later on in the series after Tomoru becomes more accustomed to Akari and Itaru's relationship and marriage.
Akira is Hikari's nephew who enjoy playing kancho with each other. Akari says that when Hikari was young, he looked exactly like Akira, but Hikari wants his father's opinion when he awakens.
Itaru is Hikari's brother in law. At first, Hikari never forgave Itaru for dating Akari because he was from the surface. But after learning about their relationship, Hikari comes to understand that there's no difference between the people from the sea and those from the surface.
- The name Hikari means "light" (光).
- Hikari's surname Sakishima means "before, ahead, previous, future, precedence" (先) (saki) and "island" (島) (shima).