Kozue runs away in shock at the sight of the twins making love, 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. That afternoon Haruka awakens to find Sora missing and her room in a mess. He goes looking for her after receiving a text from Sora which sounds like a suicide note. Nao even helps him in looking for her everywhere, mentioning to him about her confrontation with Sora, saying she has seen the two making love that summer day, and that “now they are even.” Haruka then remembered the lake Akira mentioned the other day. Haruka finds Sora, and his attempt to stop her from going deeper in to the lake nearly ends in them drowning. Days later the two leave the place to live together overseas in the city where an artisan who had connection with their parents lived, hoping to find happiness elsewhere. Though Kozue disagrees, Nao believes they will do just fine.

Haruka takes Nao on a date again, but he cannot shake the sight of Sora masturbating that night off from his mind. Eventually Haruka hits his limit and tries to get rid of those thoughts by taking Nao to a hotel, but she rejects his act and asks if he really loves her. Haruka is unable to answer and returns home. Soon after, Sora gets a fever and Haruka stays home to take care of her. That evening, Sora, with her fever subsided, confesses her feelings to Haruka and the two make love, beginning a relationship. This did not go unnoticed, as everyone, especially Kozue and Nao, begins to see the twins spend more and more time with each other. One afternoon, when Kozue and Nao decide to visit the Kasugano residence, they catch the twins in the middle of making love.

This episode replays to the event where Haruka is trying to talk to Sora about his relationship with Nao, but this time 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.

Sora decides to follow everyone at the beach, but at the moment she got off the bus, news that a young man was rescued from drowning unconscious. As Sora looks over, she finds out that the boy in question is Haruka. However, Nao acted quickly and performed mouth-to-mouth resuscitation. With that event, Sora becomes even more insecure, eventually telling Haruka not to leave home and tells all sorts of excuses just to make him stay. One day, Sora made Haruka choose between her and Nao, but he just shrugs it off and proceeds to school with Nao as if nothing is wrong. That afternoon Haruka finds Sora missing after receiving a text from her saying “Let’s leave here.” Akira, Kazuha, and Ryouhei joins Nao and Haruka in search of her, until, amidst the rain, Nao finds Sora at the bus stop. Refusing to go with Nao, Sora runs out of the bus stop, angrily telling her that she is the reason why Haruka has changed. Suddenly, a bolt of lightning strikes the bus stop and burst into flames. Sora then remembers she forgot her stuffed bunny inside. Nao rushes in to retrieve the only memento Sora has of her mother, causing her to be nearly trapped inside. After receiving the rescued item, Sora reveals to Nao her insecurities with her, that she is afraid Haruka would leave her alone. The next night, Sora joins everyone during the Summer Festival at the shrine. This time, Sora is more receptive of Nao.

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.” She then throws the curry they cooked down the drain, as she only wants Haruka’s cooking. Nao is desolate after that, and though she wants to see Haruka, she has to hide because Sora is always nearby. However, Haruka is always optimistic Sora will forgive and accept them both, as he, after knowing from Ryouhei that she changed, wants Nao to return to being a cheerful, caring, and lighthearted person. Sora lightens up a bit to the sight of Haruka and Nao being together, but still has some resistance, and prefers to distance herself from the two. It is for this reason that she never joined Haruka and Nao along with Ryouhei, Kazuha, Akira, and Motoka for the annual summer trip to the beach.

This episode replays the event where Sora asks Haru to take her measurements so she can have a uniform made. The next day Nao comes over to bring Haruka some mosquito repellent, since Sora is scared of mosquitoes, and then leaves almost immediately. The next day Ryouhei invites Haruka to the school rooftop to take a peek at the girls cleaning the pool. Haruka warns Ryouhei, though, not to peek at Nao, and leaves. Much later Ryouhei tells Nao that Haruka, “the prince she has been waiting for,” has a crush on her; but she thinks he does not like her. The truth is that something happened between the two many summers ago: Nao, trying to escape the noise of her arguing parents, ran to Haruka’s house. At that time Haruka was sleeping at their veranda, and was surprised to see Nao on top of him with her clothes undone. Until now Nao feels guilty for what she did. However, Ryouhei, even Akira and Kazuha, is into the act of bringing Haruka and Nao together. They did so by making the two meet at school pool on a Sunday. When they were changing after the swimming lesson, Haruka rushes into the girls’ locker room when Nao was scared by a black cat inside a box. The school supervisor hears their chatter, but the two were able to hide inside a box before he catches them. Thinking it was just the cat, he leaves. There, Nao gets to know that Haruka does not hate her, only that he was just surprised at the events of that summer day, dispelling her assumptions. Meanwhile, Sora shows her hatred of Nao, whom she thinks is the reason why Haruka has been preoccupied the past couple of days, at home on her laptop.

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.

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.

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.

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.

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).

After the sudden death of their parents, Haruka and his twin sister Sora move to the house formerly inhabited by their late grandfather, in a small village they often visited as children. There, Haruka encounters several of the residents, some of whom are old friends, but Sora stays at home, refusing to go to school even as Haruka starts attending. Realizing that Haruka is growing more and more distant and slipping from her grasp, Sora goes to Haruka’s room at night and appeals to Haruka as she removes her clothes…

Renji reflects over his past memories with Chihiro and is still very depressed over what happened with Chihiro throwing away her diary entries that contained accounts of Renji. After talking with Yu and Kuze, Renji starts collecting the missing diary pages; he only manages to find a handful of them. He takes them to the train station where he and Chihiro first met and finds her still sitting there. Renji discovers that Chihiro has not forgotten about him since she could not stop thinking about him for thirteen hours. Renji promises that they will always be together. The rest of the story concludes with showing scenes between Renji with Chihiro, Hiro with Miyako, and Kyousuke with Kei. Yuko finally reunites with Yu at the old church.

Chihiro finishes her novel and wants Renji to read it, though she does not want to be around when he does. Renji proposes they go out on a date, which Chihiro happily agrees to, though she promises Renji that they will become lovers for only one day. After their date, Renji confesses his love to her once again on the school rooftop, and shortly after they make love while still on the rooftop. Later that night, Chihiro gives Renji the novel to read, and she goes up to the school rooftop to wait for him to finish. After realizing the bleak ending of the novel, Renji runs up to the balcony to meet Chihiro, though she tells him that they should break up while she can still love him with all her heart. Chihiro throws all her diary pages containing accounts of Renji into the air, effectively forcing Renji to break up with her.

Kyosuke confronts Hiro about what happened with Kei, telling him that he always does things halfway. Miyako calls Hiro to tell him that it is too painful to be with him since she does not want to be eventually forgotten by him. Hiro goes to see Kei and is able to come to an understanding with her, even though he is in love with Miyako. Right before she is going to leave town, Miyako calls Hiro one last time. The calls cuts out at a pivotal moment, which leads Hiro to rush out on his bike, managing to find her at a public public telephone booth near a church where they kiss.

Hiro finds Miyako at a public telephone booth in town and after a stroll on the beach where they kiss, Hiro takes her back to his place where they make love. The following morning, Kei finds Miyako in Hiro’s bed, which causes her to run away in tears, eventually collapsing on the road as Kyosuke rushes up to her with his bike. Renji continues to stay with Chihiro despite the pain he feels and manages to smile when around her. Chihiro rereads her diary three times and eventually comes to act like the person described in her diary, but she thinks that person is already dead. After hearing this, Renji vents his frustration and continuously repeats that this is not true.

Frustrated that none of her voice messages made it through to Hiro, Miyako tossed her cell phone into a nearby fountain the night he stood her up. Hiro tries to call her repeatedly, but could not get through due to this. Miyako later calls him on a public phone and is reassured that Kei lied to her when she said Miyako had already disappeared from Hiro’s heart. Renji and Chihiro continue work on the novel, and Chihiro is pushing herself with stress and lack of sleep so as to prolong her memories. She eventually collapses and is unconscious for over thirteen hours. When she finally awakes, Renji witnesses Chihiro’s frantic state of not understanding why she has grown older or what happened to her left eye.

Renji and Chihiro continue work on the novel at his school’s library and they manage to nearly complete it. Afterwards, the two take a walk on the beach and Chihiro suddenly asks Renji if he wants to kiss her. This seemingly simple act throws Renji off balance and says that their relationship is not like that, which causes her to run away in tears. Renji breaks down, hoping she will not write down what just happened in her diary. The story shifts to a flashback of when Miyako was waiting for Hiro to show up for their date in the previous episode. Miyako continues to send him voice messages on his cell phone, first being angry for him not showing up, but later becoming increasingly desperate with each call as she does not want Hiro to ignore her. The story shifts back to the present in Hiro’s room, with Hiro and Kei together. After Hiro leaves his room to get food, Kei discovers Miyako’s messages before Hiro learns of their existence, and promptly deletes them, as she vowed to erase her from his memories.

It turns out that Kyosuke asking Kei out was a ploy on his part as a lead in to ask her if she wanted to star in an amateur film he is making for an upcoming film festival. Hiro and Kyosuke get into an argument over the differences between being a professional and an amateur, however Kei interjects in her indecision on whether or not to be cast in Kyosuke’s film. Later, Kei informs Miyako in an intense discussion that Miyako will eventually disappear from Hiro’s heart. On Sunday, Kei gets hurt at the basketball match, and Hiro ignores his date with Miyako in order to make sure Kei was all right. Meanwhile, Chihiro continues to write her novel, and Renji helps her by borrowing a uniform from Kuze so that they can enter the school’s library to research materials for the novel.

Renji brings Chihiro to his home where she meets his mother Sumire Aso and his neighbor Shuichi Kuze, though she has merely forgotten the latter many times over. After they eat, Chihiro gives Renji a notebook with her notes for her novel which he reads after she leaves for the day. He finds that the novel is rather depressing and representative of Chihiro’s life. At school, Kei tries to get Miyako to leave Hiro alone so he will not have to repeat a year of school, but Miyako talks down to her the entire time. Kyosuke films Kei in the morning while she is taking a basketball shot, and she punches him in the gut for filming her without permission. He later asks her to go out with him via Hiro’s help.