Mar is a character from the second Keroro film, a Maronian from the water planet Maron. She serves as the loyal attendant and right-hand of Prince Meru, the last prince of the Maronians. Her background ties to the ancient Maronian expedition to Earth, which left only Meru and herself as the surviving members of their civilization. She initially appears as an antagonist, assisting Meru in capturing Natsumi Hinata to serve as their new princess, as part of their plan to rebuild their world by flooding Earth. However, as the story progresses, her role shifts toward that of a protagonist.

Mar is characterized by a calm, dutiful demeanor, showing unwavering loyalty to Meru. She is highly capable in combat, demonstrated when she easily defeats Giroro in a fight, revealing her formidable physical skills. Despite her initial antagonistic actions, she is not inherently malicious; she is motivated by a deep desire to restore her lost home and support her prince. Her personality softens as she observes Natsumi’s kindness and begins to recognize her own unspoken feelings for Meru.

Throughout the film, Mar’s motivations evolve from simply following Meru’s orders to acting out of genuine care for him and for the wellbeing of those around her. She grows from a stoic enforcer into a character who helps the Keroro platoon rescue Natsumi and ultimately accepts her own role when Natsumi passes the princess title to her. This allows Mar and Meru to leave together to start anew on Maron.

Her key relationships include her close bond with Prince Meru, whom she protects and serves; a grudging respect for Natsumi, who becomes a catalyst for her change; and a confrontational but ultimately cooperative dynamic with the Keroro platoon. Her notable abilities include expert hand-to-hand combat, resourcefulness in underwater environments, and likely a familiarity with Maronian technology, though the film focuses more on her physical prowess and loyalty rather than specific supernatural powers.