Onashia is the High Priestess of the Tempus Spatium, and presides over the gender selection ceremony at the Spring. Daikuurikans are born female, and choose a sex at age 17; in Simulacrum, this is done by going to the Spring at the temple of Tempus Spatium. As head of Simulacrum's High Council, she serves as head of state.   ~! it is hinted that Onashia is actually Dominura.In Dominura's last scene, while she walks, we can see sparkly gold flakes in the ground, like the ones that Onashia shows Yun. When Onashia dissappears, Yun calls out Dominura's name as she peers into the Spring.!~

In the peaceful theocracy of Simulicram, everyone is born female. At age 19, each maiden undergoes a special ceremony where she chooses her sex. However, only Pairs of maiden priestesses can synchronize with the ancient flying ships known as Simoun needed to defend Simulicram. These Pairs refrain from undergoing the ceremony as long as they wish to keep piloting their Simoun. 
Aer is recruited to be a Simoun pilot after a terrifying attack by an enemy nation decimates the squadron known as Chor Tempest. To earn her wings she needs to find her way into the heart of Neviril, Regina of Chor Tempest. But Neviril's heart still belongs to her previous Pair, lost in the battle when she attempted a forbidden Simoun maneuver. 
(Source: Media Blasters)

Married to voice actor [Shuuichi Ikeda](https://anilist.co/staff/95598/Shuuichi-Ikeda)

An alternate comedy version of Simoun.