Urii occupies the twelfth position among the twelve protectors as their boar spirit, a role assigned after placing last in the legendary Zodiac race. He stands as the youngest and sole child within the group. His pampered upbringing fostered underlying loneliness despite privilege, initially manifesting as frequent crying when frightened or overwhelmed. This emotional vulnerability unlocks his unique combat ability, the "Whee Blast," where his chest-mounted badge discharges a powerful, uncontrollable energy beam coincidentally resolving critical mission situations whenever he weeps.

Urii undergoes significant personal growth across the series, culminating during the final conflict against the primary antagonists. While the Jyarei Queen Nyanma kills most team members, Urii survives alongside Bakumaru and Cream through circumstance and quick thinking, including taking cover behind others during a catastrophic explosion. In this climactic phase facing the ultimate enemy Bagi, Urii demonstrates uncharacteristic bravery by enduring intense threats without crying, directly aiding the team's efforts. His development culminates in participating alongside the other revived Rangers in the united "ZODIAC PUNISHER" technique that ultimately defeats Bagi.

Urii possesses elemental associations with Water. He belongs to the same trine as Cream and Souffle and shares a seasonal affiliation with winter alongside Bakumaru and Hols. His designated time within the Chinese zodiac cycle falls between 9 PM and 11 PM. A recurring theme underscores his background: a persistent sense of isolation despite outward comfort, hinting at deeper emotional needs. His character theme is "Ururu Urii Sweet Teardrop."