TV-Series
Description
Mayu Oyama is the daughter of Tochiro Oyama, chief builder of the starship Arcadia, and Emeraldas, a prominent Leijiverse figure. After Tochiro's death and Emeraldas' departure, Captain Harlock became her guardian, honoring a promise to protect her. Safety concerns necessitate her residence on Earth, moving between locations like a Christian boarding school and a secret area in Egypt.

Physiologically, Mayu is a human and La Metalian hybrid, inheriting half her DNA from each parent; her awareness of this lineage is unclear. Her appearance typically includes light blue hair, brown eyes with lashes, and a standard outfit: a white turtleneck shirt, red overall dress with a green bow, black Mary Jane shoes, and white socks.

Despite enduring hardships like parental absence, bullying, and threats from forces such as the Mazone, Mayu exhibits resilience and optimism. Her positive outlook influences others, notably Captain Harlock, who values her as a symbolic connection to Earth and Tochiro's legacy. A key personal item is an ocarina gifted by Harlock on her seventh birthday; its melody became known as "Mayu's Theme."

The Mazone, seeking to reclaim Earth, identify Mayu as Harlock's vulnerability. Queen Lafresia initially rejects using her as a hostage but later authorizes her kidnapping to divert the Arcadia. This triggers a pivotal story arc where Harlock and his crew commit to rescuing her across the universe. During captivity, she is held at a boarding school infiltrated by Mazone agents, including a dorm dean posing as human. Harlock exposes and eliminates the dean in Mayu's presence.

In the film *Space Pirate Captain Harlock: The Mystery of the Arcadia*, Mayu features in an underwater battle narrative paralleling the folktale "Urashima Taro," diverging from the main series. In later OVAs like *Endless Odyssey*, her significance endures as a motivator for Harlock's actions, reinforcing her role as an emotional anchor. Her hybrid heritage and familial ties position her as a nexus connecting key characters and factions across the Leijiverse.