While at home, Shinichirō Nakagami laments how he cannot express his feelings for Hiromi Yuasa. He notes that when he knew her before he always treasured her smile, but now she acts coldly at home, and Shinichirō regrets not being able to see her tears or any form of significant emotion. At school, Shinichirō sees a girl named Noe Isurugi, and after criticizing her for interacting with chickens, is cursed by her. Shinichirō is quickly beset by bad luck for the rest of the day, and even sees Hiromi undressing to take a bath. To atone for what he said to Noe, he crafts a chicken out of a tissue box for her. The next day he gives the box to her, but she is saddened because one of the chickens, Raigomaru, has been killed. As Shinichirō notes that she did not cry, she tells him she has given her tears away.

After insisting Shinichirō should believe her about giving her away her tears, Noe tells him of her mission to retrieve them. At school the following day, Noe starts paying extra attention to Shinichirō, such as waving to him while in P.E., and giving him seeds previously intended for Raigomaru. Hiromi notices this and tries to approach Noe on her own, but cannot communicate with her. Later, Hiromi asks Shinichirō to introduce her to Noe, but after Noe learns of this she approaches Hiromi herself. Noe instantly sees through her guise, and although she can tell that Hiromi does not like her, is not angered. Hiromi later recounts this meeting to Shinichirō, confirming that she did not want to be Noe's friend to begin with.

When Shinichirō goes to school, he finds red seeds in pink envelopes which Noe has placed in his locker, desk, and around the classroom. When he goes confront her, he finds Noe being picked up by a boy he assumes is her boyfriend. The next day, he finds red seeds leading from his classroom to the tree outside where Noe is. He tries to tell her to stop, but Noe says that is not something for him to decide. She jumps out of the tree, and Shinichirō has to carry her to the boy's basketball game currently in action. The same boy Shinichirō saw pick Noe up after school is playing in the game, and it is revealed that he is her older brother. Shinichirō overhears Hiromi's friend, Tomoyo, ask her if she likes Shinichirō, but Hiromi says she in fact likes Noe's brother.

While walking back to Shinichirō's house, Hiromi tells him about her crush on Noe's brother, which hurts Shinichirō. The next day, he leaves early in order to avoid Hiromi. Later, Aiko approaches him while he is resting on the seawall, and she eventually persuades him to go shopping with her. At lunch, Shinichirō tells Aiko about her giving him false hope in his relationship with Hiromi. Aiko tries to cheer Shinichirō up, but to no avail. When he goes home, Hiromi asks Shinichirō if he is avoiding her because of what happened, and Shinichirō replies in a way that hurts them both. The following day, Noe drags Shinichirō around town and explains why she is gathering tears, and in the process manages to cheer Shinichirō up. In the morning, Shinichirō apologizes to Hiromi for the events of the previous day. Concentrating on the apology, he accidentally uses face wash instead of toothpaste when brushing his teeth; Hiromi and Shinichirō both laugh at this. Shinichirō is happy he was able to make her laugh. As he is walking out of his house, Noe's brother is waiting for Shinichirō and introduces himself as Jun Isurugi. They exchange greetings, and Shinichirō is stunned when Jun asks him to go out with Noe.

Shinichirō looks for Noe during school, but after she suggests they eat lunch together or go home together, he becomes defensive and lies, telling her that he has dance practice after school and that she should eat with her friends instead of him. After school another day, Noe drops in on Shinichirō in the middle of dance practice, and he later becomes inspired by her. Noe's older brother Jun pays Shinichirō another visit and during their exchange Shinichirō suggests that Jun go out with Hiromi if he is asking him to go out with Noe; Shinichirō becomes nervous that Jun may actually go through with it. Shinichirō goes to tell Hiromi about Jun saying she was cute, but she gets annoyed at Shinichirō for coming into her room to tell her something like that. Meanwhile, Aiko has started to knit a sweater for Miyokichi, but she is showing Shinichirō more affection than him.

Aiko tries to tell Shinichirō her feelings but is interrupted when Miyokichi arrives. Miyokichi later goes shopping with Aiko and the latter stomps out of a shop flustered and tells Miyokichi that she bought the sweater that Shinichirō had picked up before. Miyokichi gets the hint and feels troubled. While frustrated about Jun approaching Hiromi during school, Shinichirō asks Noe to stop bothering him for while and ends up getting his belt being pulled out by Noe. Jun goes out with Hiromi on a date Sunday, and after they arrive back at her home, Jun tells her that Shinichirō and Noe are going out together. Later that night, Shinichirō overhears Hiromi and his mother's quarrel and has a tussle with his mother and Hiromi. Subsequently, Shinichirō finds out from Hiromi that he and Hiromi might share the same father.

Noe once again tries to approach Shinichirō at school, but he shrugs her off, telling her that she does not understand his situation. Following this, Noe seeks out Hiromi but gets in a short fight with her while at school. Shinichirō realizes that Noe does like him a lot, due to all the attention she gives him, and after a little more persuasion from Jun, Shinichirō asks Noe to go out with him, albeit while somewhat embarrassed and looking away from her. Noe even asks him to say it again properly to her face, and write out "I love Noe" on the ground with stones. After school, Shinichirō goes to see Aiko at her shop, and when he tells her that he is now going out with Noe, Aiko rushes up to him and kisses him. While shedding tears, Aiko asks Shinichirō to consider her as well.

After asking Noe out, Shinichirō tells her about his picture book that he is making about the rooster Raigomaru. Aiko cannot get over what happened with her and Shinichirō. Noe's brother goes out on a date with Hiromi, and she finds out the true reason why Shinichirō is going out with Noe and also why she is going out with Noe's brother. Hiromi cuts her date short after she speaks her mind to Noe, though she realizes that she acted liked Shinichirō's mother since she shows resentment towards Noe. She asks Noe's brother to give her a ride to a "town where it does not snow" in order to get away from things.

Jun and Hiromi crash while on the motorcycle, but they are not harmed. As a result of the accident, both Jun and Hiromi get suspended from school. Shinichirō's mother, who had previously shown hostile attitudes towards Hiromi, finally accepts her as her own child, and tells Hiromi that she made up the story about Hiromi being her husband's child. Shinichirō talks with Noe and gives her an update on the picture book. Noe hints that she knows where Shinichirō's true feelings lie, and she runs off back home.

Shinichirō hears from Miyokichi that he broke up with Aiko, even though he did not want to accept it at first. Miyokichi goes to Noe to try to get her to put a curse on him so that he does not fall in love with anyone again. Now that Hiromi knows she and Shinichirō are not siblings, she grows happier at home, and goes to see Jun to break off her relationship with him, but he does not want that. Aiko finally gets over the fact that Shinichirō does not think of her in a romantic way and tells him that she is moving on from him. Hiromi decides to move out of Shinichirō's house, and as she is driven away in the moving truck, Shinichirō gets on his bike and races after her. When he finally catches up, Shinichirō slips and falls off the bike; the driver stops the truck and Hiromi runs out towards Shinichirō but trips and falls onto him. Shinichirō tells her that he will do everything properly from now on.

It has been a week since Hiromi moved out and in the meantime has settled into single living. Miyokichi gets a call from Aiko, and the two decide to start over from the beginning as friends. During a basketball match where Hiromi is getting purposely fouled by the other team, Jun comes into the match and asks the opposing team what was the meaning of their behavior, which sparks interest from spectators. Hiromi meets with Jun in the park where he apologizes for what happened during the game. Hiromi once again tries to break it off with him, but he still does not want to. Noe does not come back home at night, and Jun calls Hiromi to tell Shinichirō about it, and he leaves to look for her. Shinichirō finds her at the beach with the chicken Jibeta.

After Shinichirō listens to Noe talk to herself at the beach, he goes home but is unable to sleep due to her words. The following day is the festival, and despite not getting any sleep, Shinichirō does the dance perfectly with all the others. Hiromi tries to tell Noe to leave her and Shinichirō alone, though she still comes to watch Shinichirō dance on stage. Afterwards, Shinichirō blows off Hiromi to go search for Noe so that he can tell her that he finished his picture book. When he finds her at school up in the tree where they first met, Shinichirō watches from afar as she jumps off into the snow below.

The day after the festival, Shinichirō goes to Jun to apologize for Noe's broken leg, though Jun says he will not forgive him. Jun later sees Hiromi and breaks it off with her, saying that he never loved her, not even a little bit. Shinichirō decides to show his picture book to Noe, but she refuses, so he says he is going to throw it into the sea, which he does by ripping out the pages and making them into paper airplanes. Noe interferes and they manage to recover all but the last page, but Noe looks at the rest of them. Shinichirō and Noe part with him telling her that while he is in love with Hiromi, his heart wavers when he looks at Noe. Shinichirō goes to see Hiromi at night and tells her that he will always be with her. Several months later in the spring, Noe is finally able to shed tears for the first time in years.