Taro Mitsuki

He was the music teacher at Lucia, Hanon, and Rina's school. Hanon had a huge crush on him ever since the first time she saw him. He had a relationship with Sara years ago but there was an incident and Sara transformed into a black mermaid because of the hate she had towards him. Later on, Tarou revealed why he left Sara: because she was the orange pearl princess and had a lot of responsibilities, and he didn't interfere with that. She forgave him, but decided to die with Gaito in the end. When he was getting ready to leave the country after Sara perished, Hanon confessed to him, and he kissed her on the cheek and gave her the song sheet that he wrote for her, which ended being Mizuiro no Senritsu, one of Hanon's image songs.