Kirius Rakus Lestrine Ha hails from the planet De Metrio, serving as a pilot in the KISS organization commanded by Villagulio. He operates alongside comrades Izo and Arei, forming a close-knit team while piloting the distinct black-pink mecha unit, the Ovid Libertas. Outwardly serious and reserved, Kirius nonetheless possesses a fascination with Earth's customs, occasionally drawing unconventional conclusions about them—a curiosity contrasting his typically calm disposition.

As the oldest and most experienced among his immediate peers, Kirius initially functions as an antagonist aligned with Villagulio's objectives. He demonstrates loyalty to his comrades but is also susceptible to being drawn into reckless or nonsensical actions by Villagulio's unpredictable behavior. After the resolution of major conflicts, specifically following Villagulio's second skirmish, Kirius undergoes significant development. He transitions away from military engagement and relocates to Earth, settling in Kamogawa. There, he secures employment at Hiroshi's beachside cafe alongside Izo and Arei.

In his new role, Kirius works as a waiter dressed in butler-themed cosplay. His presence notably attracts a substantial female clientele, contributing significantly to the cafe's commercial success and surpassing the performance of Hiroshi's original restaurant. This shift showcases his adaptability and willingness to embrace civilian life. Beneath his quiet exterior, Kirius maintains a warm aspect to his personality, which becomes more apparent during his interactions within the cafe environment. He is identified as 19 years old, with dark blue hair and blue eyes.