Summary:
Vander Decken IX learns about the Tamatebako and wishes to use it to age Shirahoshi when she grows up a bit. Otohime returns with a letter from the world’s nobles and all the citizens finally begin to give their signatures after so many years of work. At the palace, Otohime explains to her sons about Shirahoshi’s ability to summon sea kings and how if she loses control, she can destroy the island. The princes swear to protect their sister.
In the square, someone sets fire to the autograph boxes, and in the confusion, Otohime is shot dead. In her final moments, she tells everyone to hate the shooter and Fukaboshi promises to keep her dream alive. Otohime and her children touch their pinkies one last time and she dies.
Decken hears about the Tamatebaku and tells his men to get them for him, and when they can’t, he decides to wait a few years until Shirahoshi gets old. Otohime returns and explains that the world nobles have a lot of influence in the world and they returned with their signature and all the citizens end up giving her their signatures for her cause. She celebrates with her children and husband. At the palace, Otohime explains to her sons about the Sea King incident and how Shirahoshi summoned them. He explains that mermaids have the ability to communicate with fish, however, the mermaid princess of legend is able to communicate with sea kings. He states that this power is capable of creating great good for the world, but in the wrong hands it can destroy the world if used incorrectly. He also explains that Shirahoshi is not aware of this ability and if she were to lose control of her emotions one day, she could destroy the island. Otohime asks his sons to become strong warriors and protect his sister, and they all agree.
In the square, someone has set the autograph boxes on fire, and Otohime asks to try to save them. During the confusion, someone shoots Otohime. Jinbe and Alladin tell the soldiers to find the shooter and take care of her children. Fukaboshi and her children rush to her side. Shirahoshi is stunned by what happened and Decken comes and tags her with his Mato Mato no Mi powers and leaves. Fukaboshi swears revenge on whoever did this, however, Otohime asks that she not hold and hate the shooter so that their hatred doesn’t continue to spread across the island, saying that she let her guard down because she was happy. Shirahoshi begins to pass out and Ryuboshi and Manboshi remember what their mother said earlier and as Shirahoshi loses control the two brothers start dancing and singing to calm her down, declaring that they will always watch over their sister while everyone else is shocked by what they do. Fukaboshi tearfully promises her mother that they will start over and keep her dream alive so she doesn’t have to worry and protect Shirahoshi. Otohime is happy and everyone touches their pinkies one last time and Otohime dies.