That love transcends a hundred years――. After receiving a confession from Yuitsuki triggered by an earthquake, Tsumugi finds herself troubled about the future. What answer will Tsumugi come to? As Yuitsuki's engagement is also decided, the time they have left is dwindling, and an event that will greatly shake their relationship occurs…!? A love story woven by a Reiwa high school girl and a Taisho noblewoman, the emotional concluding volume!