Character Information: Love Interests
Mitsuki Tarou | 
Mitsuki-sensei is the new music teacher at Lucia's school. Because he's so young, he easily becomes friends with his students, especially one Houshou Hanon. Mitsuki-sensei treats Hanon like a close friend, and seems oblivious to the fact that she likes him... She really, really likes him. But Mitsuki-sensei, also, has had encounters with a mermaid in the past...
Ultimately, Hanon does the right thing, and gives up on Mitsuki-sensei when she finally accept the fact that he is already in love with another. Mitsuki-sensei seems to finally realize the depth of Hanon's feelings for him, but fortunately, her mature self-restraint saves him from having to outright break her heart. At the end of the first story arc, Mitsuki-sensei leaves Japan to study music in Germany. Although he is apart from Hanon, the two of them keep in touch with letters. What started as a passionate crush on Hanon's part eventually develops in a deep, strong, lifelong (and entirely platonic) friendship between teacher and student.
Name Notes: "Mitsuki" is written with the kanji characters for "ocean" and "moon."
Hamasaki | 
Hamasaki is a teasing, flirtatious boy whom Rina first bumps into in chapter 15. It's obvious to everyone else that Rina and Hamasaki have mutual crushes on each other, but Rina adamantly denies it, and Hamasaki's flirting drives her up the wall. Hamasaki is a high school student who wears glasses and rides a motorcycle. Other than that, the manga reveals almost nothing else about this mysterious boy, not even his personal name ("Hamasaki" is his surname.)
Hamasaki and Rina at first only run into each other by accident. Hamasaki tries to get Rina to open up to him and tell him what's on her mind, but she remains silent around him. Ultimately, however, it IS Rina who approaches Hamasaki with an invitation to their first date-like outing: watching the fireworks together on the night of a summer festival. However, even as Hamasaki and Rina see each other more and more, Rina still won't tell Hamasaki what's on her mind. Finally, Hamasaki grows frustrated, and confronts her about it. "You won't show me your heart... I know that you're hiding something from me!" he tells her.
Later, Hamasaki takes Rina to Awami Shrine on Christmas Eve, and tells her that he's a descendant of the man who was saved by the legendary mermaid. "It must seem silly for a high school student to still believe in mermaids... But when I look at you, I just can't help but believe." Hamasaki starts to tell her that he loves her, but Rina screams at him tearfully, "STOP!" So instead, the two hug. "Don't say goodbye to me," Hamasaki pleads to Rina. And Rina vows to him, silently, Someday, I'll return to you.
The final chapters of the manga show Hamasaki and Rina happily hanging out as boyfriend and girlfriend. Rina knows that someday she will leave Hamasaki, but she seems to have made peace with that fact. Hamasaki, as well, is more perceptive than he lets on - he seems to understand the reason for Rina's silences, and has also made peace with the fact that she is keeping secrets from him. But still, he is able to love her just the same.
Name Notes: Hamasaki's given name is "Masahiro." The only place this is revealed in the manga is in Hanamori Pink's introductory notes to chapter 25, published in volume 05. "Masahiro" was named after one of the chief editors of Nakayoshi magazine.
Shiroi Nagisa | 
Nagisa is a young boy who falls head-over-heels in love with Hanon, despite the fact that she regards him about the same way that she would regard a cockroach that she found crawling in the bathtub. Hanon often declares (to anyone who will listen) that she only has taste for older men, after all. Nagisa is utterly sincere in his attempts to win Hanon's love, although his "romantic" stunts usually backfire, and end up only infuriating Hanon. Still, you have to give the poor boy some credit. He's literally willing to do anything, if he thinks that it will make Hanon like him.
It is not until chapter 25 of the manga, however, when Nagisa literally puts his life on the line in order to protect Hanon, that Hanon finally admits to herself that Nagisa might be "kind of cool." Finally, Hanon begins to see Nagisa more and more as an adult. However, Nagisa panics when he discovers that Hanon was once in love with her teacher, Mitsuki-sensei, and that the teacher even wrote a song just for Hanon. Nagisa eventually discovers that Hanon has received a letter from Mistuki-sensei, her "beloved." Nagisa drags Hanon out to the beach and, as they crouch on the sand in front of the waves, confesses his love to her. Then he immediately looks away and says, "But because I love you, I understand your feelings. You still love that guy who wrote that melody for you, don't you? I don't have any talent like that. My love is just an bother to you, so if you want me to, I'll give up--" Seeing how grown-up Nagisa is, Hanon starts crying. "If you really love me, why don't you try to make me forget about Sensei?" she asks him. It turns out that in Mitsuki's letter, all that he really wrote was words of encouragement to help Hanon move on with her life. Haven't you found someone with eyes only for you yet? Mitsuki wrote in his letter. Hanon confesses all of this to Nagisa, and Nagisa then promises: "I may be just a kid, but Hanon, I swear, I'll become a man that you can be proud of!"
On Christmas Eve, Hanon gives Nagisa a pair of tickets to a concert by Mitsuki-sensei, to be held in Japan next year. She tells Nagisa, "I want to introduce you properly to Sensei, as my boyfriend... I mean, it's already been half a year, and Sensei has become so famous, it'll be embarrassing if I couldn't even manage to get myself a boyfriend in that time..." Nagisa seems embarrassed, but Hanon smiles at him and says, "Don't worry! 'Cause you're the one that I love, you know." Blushing, Nagisa gives her an aqua-colored barette for her hair. As he puts the barret in her hair, Hanon realizes that Nagisa has grown taller than her. Finally, she kisses him.
The final chapters of the manga show Nagisa and Hanon happily hanging out, as boyfriend and girlfriend. Hanon realizes that she will have to leave Nagisa someday and return to the ocean - but she seems to have made peace with this fact. Nagisa, however, does not seem to understand that someday Hanon will leave him. The manga leaves this issue completely unresolved.
Name Notes: "Nagisa" means "beach". "Shiroi" sounds like the Japanese word shiroi ("white"), but is actually written with the characters for "white" and "well" (as in, a drinking well).