Yosuga no Sora

Kozue runs away in shock at the sight of the twins having Intercourse, while Nao calmly left the scene, but Sora wouldn't even care. Haruka thinks of ditching school, but she tells him to think little of it. Kozue tells him the next day that she'll never talk to him again, while Nao effectively ends her relationship with him after his apology. That night Haruka fights with Sora when he tells her that they stop doing it, even inadvertently hitting her. Things get complicated when they find out that their parents left no money for the two, and in order to survive they have to be taken under custody of their relatives, but this means them living apart.

Haruka is trying to start a new life over with Nao, but Sora is always at the back of his mind, since, lately, she seems not to accept Nao, and that she seems to be teasing him. Haruka suggests a date with Nao, but cannot get to tell Sora about it, even disguising it as if he will be spending time with Ryouhei. During the date, though, Nao notices that Sora is never far from Haruka’s mind, him buying things for his sister rather than for her, and eventually spoiling their date. They plan to make croquette curry upon arriving home, but is canceled when Haruka finds Sora not feeling well in her room after having a bad dream. The next day Nao notices that Haruka tries to hide his date with her from Sora, but she just went along. One night, Haruka catches Sora masturbating in her room while mentioning his name, much to his dismay—she is enamored with him ever since that one summer day in their childhood when Haruka kissed Sora while playing.

By now Sora is showing her hatred of Nao in the open, even in front of Ryohei and Nao herself. One afternoon Sora, attracted by the smell of curry cooking in the kitchen, catches Haruka and Nao making love in the living room. Sora throws Nao out of the house, warning her not to see Haruka ever again, since it is the second time she catches the two doing the "dirty deed."

Haruka enters Akira's room and stops her from burning something, which is her mother's missing journal, where it is written that Kazuha and Akira has a chance of mistaken identity. With the journal, he suggests to Yahiro and Kazuha a DNA test to prove things once and for all.

On their way home from school, Haruka and Kazuha are interrupted by a frantic Yahiro, who is concerned over the non-appearance of the always-responsible Akira as usual. They discover Akira at her home, collapsed due to exhaustion, and Kazuha proceeds to blame herself and her infatuation with Haruka for not noticing Akira's condition.

Sora asks Haru to take her measurements so she can have a uniform made, and finally starts attending school with Haruka, though she is disappointed to find that she and Haruka are in different classes. While cleaning the swimming pool as part of a mixed gym, Akira accidentally soaks Kazuha who forgot her swimsuit, and so Akira takes her to dry off. Haruka finds Kazuha's phone and goes to return it, only to overhear a sensual-sounding conversation in which Kazuha addresses Akira as "Onee-chan" (big sister).