When Kazuha realizes that Haruka has overheard their conversation, she chases him down to clear up any misunderstanding. She reveals that Akira is, in fact, her illegitimate older sister, born of a different mother. Due to her family's societal standing, Kazuha's father is not able to acknowledge Akira as his daughter, causing Kazuha to be resentful of her father and to feel a burden of guilt and responsibility towards the always-hard-working Akira. To help lift Kazuha's spirits, Haruka invites her out on a date, and they subsequently realize and admit their rapidly-progressing feelings towards each other. Meanwhile, Akira continues to try her best on her own, but collapses, apparently due to exhaustion.
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. Akira recovers a few days later, but confronts Kazuha about her abandonment of Haruka and the inappropriate sense of guilt she feels regarding their father's actions. Realizing the truth of Akira's words, Kazuha withdraws into a state of depression while struggling to determine what to do. The day of the festival arrives, and Kazuha works up the courage to appear, where she is reunited with Haruka. Haruka informs Kazuha that her father had been supporting Akira financially in secret all this time and, when Kazuha witnesses her father praising Akira, she realizes that she had misjudged him. Thus, she was able to move past her codependency towards Akira and pursue a whole-hearted romantic relationship with Haruka.
The Introduction to this episode replays the event where Haruka was standing near the girls locker room, overhearing Akira's and Kazuha's conversation, but this time, instead of walking away mislead, Akira comes out and takes the phone from Haruka. This allows for the story to have an alternative ending. Haruka notices that Akira has been acting strange lately, and decides to talk to her alone at school the next morning. He sees the sad look on Akira's face and becomes worried, and wants to help Akira find her mother's pendant (after remembering her losing it as a child). They go in search for the pendant by a tree they would play by as kids, only to Haruka's horror that the tree had been removed by a landslide. He attempts at digging around for it, but without any luck. The two go to Akira's residence to take a bath, and have a romantic moment together. From there, Haruka goes to the festival, and, after seeing Akira cry while dancing the sacred dance, rushes off to see what had happened.
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. Yahiro refuses, but, despite disapproval from her mother, Kazuha agrees. Haruka informs Akira at the shrine the next day that the DNA results will be out in five days, but Akira disappears on the fifth day. Haruka finds her at the train station, where they talk until the evening. When the DNA results arrive that night, Kazuha and Sora delivers it to Akira, who is still at the station, but she buckled, too scared to read it. It is then that Kazuha's mother appears, and tells everything at their home, where Akira is shown the lost pendant, returned to her by someone who found it at the mountains, basing on the name engraved on its back. She reveals that she and Akira's mother had shared the same hospital room, and, one day Akira pulled the pendant off of her neck as Mrs. Migiwa held her in her arms. After hearing that Akira's mother had died, she gave the pendant to her to make her feel, at least, the presence of a mother. Akira then reads the DNA results, and it read negative, which means Akira is born of a different mother. There, Kazuha's mother let her keep the pendant, and apologizes to Akira. She later confesses her love for Haruka and vice-versa.