Yosuga no Sora: In Solitude Where We Are Least Alone

Haruka and his twin sister, Sora, move to the late grandfather's house after the death of their parents.

Sora finally starts attending school with Haruka, but is disappointed to find that she and Haruka are in different classes.

Kazuha reveals that Akira is her illegitimate older sister, born of a different mother but Kazuha's father does not acknowledge Akira as his daughter.

While on their way home, Haruka and Kazuha are interrupted by a frantic Yahiro, who is concerned about Akira.

This episode replays the event where Haruka overhears Akira's and Kazuha's conversation, but this time, Akira comes out and takes the phone from Haruka.

Haruka enters Akira's room and stops her from burning the doctor's missing journal, where it is written that Kazuha and Akira has a chance of mistaken identity.