Simoun

In the island nation of Daikuuriku everyone is born female, and at 17 they choose a permanent sex. Simulacrum, a pacifist theocracy, relies on mysterious flying machines called Simoun that only unchosen girls can pilot. Those pilots, known as Sibyllae, can perform a ritual called Ri Maajon that devastates enemy forces. When industrial Argentum decides to seize Simoun technology, war erupts and the Sibyllae are pulled into unequal conflict. The fighting grants many pilots an exemption from choosing a sex so long as they keep flying. Aeru, a newcomer with a hidden past, and Neviril, leader of Chor Tempest, struggle to keep their squad together under pressure from combat, personal loyalties, and questions of identity.

Simoun premiered in 2006 and was created by Goh Mihara, Sho Aikawa, and Sho Shinoyoshi. The cast features Michi Niino as Aeru, Rieko Takahashi as Neviril, Ami Koshimizu as Paraietta, Eri Kitamura as Amuria, and Fumie Mizusawa as Wapourif.

The series did not collect major industry awards. It hasn’t been prominent in mainstream prize lists, though it continues to be referenced by fans and smaller critics for its unusual subject matter and tone.

Simoun has developed a small but committed fanbase that values its handling of gender choice, intimate relationships among the pilots, and the solemn visual style. Its episodes and imagery often spark discussion in online anime communities and among readers interested in gender and sexuality in media, and it has inspired fan art, essays, and translations across niche circles.

Viewer reception is mixed, reflected in modest user scores like a 4.9/10 rating on some sites. Many viewers appreciate the slow, atmospheric storytelling, character-focused drama, and the show’s willingness to raise moral and religious questions. Others find the pacing uneven and the symbolism dense, so it tends to appeal most to viewers who like mood, ambiguity, and slow-burning emotional conflict.