The kingdom of Freesia is a monarchy ruled by queens.
It is a kingdom where maidens form contracts with spirits.
As long as a woman bearing Freesia’s blood sits on the throne, the country enjoys a proper climate, free from natural disasters, and abundant harvests.
At the heart of the kingdom lies the royal capital, Luchido, where the queen and the princess reside.
The princess’s name is Rubellieve.
Far away in the Sissaya region, the protagonist, Roberi, was raised.

One day, someone from the castle visits Roberi.
It is a sage who oversees the political core of the castle.
He delivers a shocking truth to Roberi:

“I have come to escort you, Princess.
You are the twin sister of Lady Rubellieve—
Robelist Freesia.”

Every girl born into the royal family bears a crest somewhere on her body as proof of her contract with a spirit.
Roberi’s crest appeared on her buttocks.

But why summon her to the castle now—?