Yu-no

The central character of the story, Yu-no, is the daughter born between Takuya Arima and Sayless. Her name was given by Takuya, inspired by the phrase "You know?". As an adult, her measurements are 86-58-86 (cm). She appears at the beginning of the story, though her true identity and relationship with Takuya are revealed in the latter half of the narrative. While traveling towards the Imperial Capital with Takuya, she is captured by imperial soldiers after visiting a temple. Later, she reunites with Takuya in the Imperial Capital, but Yu-no has been elevated to the status of a priestess and is brainwashed, causing her to forget Takuya. After her brainwashing is undone, in order to prevent the collision of events, she offers herself to the synchronization ritual with Grantia. On the night before the ritual, she forms a special bond with her biological father, Takuya.

In the adult anime adaptation, even after reuniting in the Imperial Capital, Yu-no never regains her memory and continues to forget Takuya. In the final scene, she begins to recognize Takuya not as her father but as a single man, and, as with Kanna Hatano, there are no incestuous scenes depicted.