The Sugimoto family, a lineage of samurai descent, has a long history of honoring the bonds between women to ensure the continuation of their bloodline and maintain order. The male head of household, though nominally in charge, is in reality not the one who upholds the family's legacy. Instead, it is the mother-in-law and the daughter-in-law who secretly carry on a sacred ritual—one that goes beyond mere ceremony, serving as a purification to refine their inner selves. This ritual also plays a crucial role in confirming reproductive vitality. And now, at this very moment, I am about to spend my first night with Riho-san, under the traditions of the Sugimoto household.