Name: Siva Height: 185cm Image Color: Yellow-green Visual (Frog Form): A mascot-like character wearing a frog hood. Visual (Human Form): Hair is parted in the center and colored yellow-green. Wears a green hoodie with light blue polka-dot pants. Personality: Kind, handsome, popular, cool, and energetic. First person: I (casual). He jokes around a lot but gets serious when it counts. He used to play with Hotaru when they were young. As an adult, he joined the Monopi clan, Hotaru's family. He was the one who originally found the map to the Rainbow Diamond, but sensing something sinister, he tore the map and jumped into the sea. However, he doesn't remember much from that time.

Japapa: Male. The reliable leader who pulls the group together. "I see, haha." "Is it...?" Noa: Female. A reliable and kind girl who loves sweets. "Is that so?" "It is!!" Tattsun: Male. The mood maker and jokester of the group, skilled at both setup and punchlines. "Why would you say that?!" "Right?" Yuan-kun: Male. Possesses extremely high gaming skills and a laid-back personality. "It's definitely that!!" "Is it?" Donuku: Male. A half-white fox character who is somewhat airheaded and cute. "I wonder if that's it?" Uri: Male. Highly talented in singing and instruments, with a cool side to him. "That's right." "I told you so, haha." Eto: Female. A frank, tomboyish, and active girl. "True, haha." "That's just too much." Naokiri: Male. Loves poppies (flowers) and has a kind, slightly mysterious worldview. "Is it?" "It is, isn't it?" Mofu: Male. The smartest member of the group, reliable and full of knowledge. "I wonder?"

Daioh Captain of the Monopi and Hotaru's father. He plans to use the diamond to power up a transformation beam and turn everyone except the Monopi into diamonds. Speech style: Blunt and authoritative. The man who actually created Happy Island. Daioh's Subordinates: Ikari Male. The Monopi's #1 close-quarters combatant. Looks easygoing but is a very strong researcher. Speech style: Polite but quirky. Zarigani Female. Has a total "gal" vibe. A sisterly character. Doesn't transform herself but fights using crayfish claws. Uni Male. Characterized by unique verbal tics. Transforms into a sea urchin to attack.