The story begins with the protagonist, Reito Otonashi, a quiet and solitary high school student, parting ways with his energetic friend Shota Ueda. Reito finds comfort in his current distance from classmates, appreciating the mutual respect and occasional assistance. One rainy afternoon, while returning home from the library, Reito encounters Shion Sakura, a classmate he barely knows, who has forgotten her umbrella. Despite his own home being a considerable distance away, Reito impulsively offers her his umbrella, lying about how close he lives. This act of kindness leads to Reito catching a cold the next day.
Shion, feeling immense guilt for Reito's illness, confides in her friends Haruno Miyamae and Rin Takara. Shion, who suffers from a significant fear of men, struggles with the idea of directly apologizing to Reito. Haruno and Rin devise a plan: they will deliver Reito's umbrella and some notes to him, and in the process, exchange contact information so Shion can apologize without a face-to-face encounter. Shion, though hesitant, agrees, touched by her friends' support.
Reito, recovering from his cold, is surprised when Haruno and Rin visit his home. They explain Shion's situation and her desire to apologize, handing him the umbrella and Shion's contact information. Reito, understanding Shion's difficulty with men, readily exchanges LINE contacts. Shion, upon receiving Reito's message, feels a mix of relief and nervousness. She sends a polite apology, which Reito accepts, assuring her he's fine and thanking her for the notes he'd received.
The following Monday, Reito finds a beautifully packaged box of homemade cookies in his desk. He deduces they are from Shion, who, embarrassed, confirms it through a text message. Reito is impressed by her baking skills and expresses his gratitude. Shion, in turn, reveals her past trauma related to men, explaining how Reito's genuine kindness made her feel safe. This leads to a more open exchange of messages between them, with Shion gradually shedding her formal tone.
The narrative then shifts to the upcoming school trip. During class, students are tasked with forming five-person groups. Shion, along with Haruno and Rin, is approached by Shota, who invites Reito to join their group. Shion discreetly messages Reito, asking if he would be willing to join their group, which he accepts. Their group is formed, and Reito notices Shion's popularity among the boys.
Later, Rin meets with Reito, expressing her gratitude for his efforts in helping Shion. She explains Shion's deep-seated fear of men, stemming from a negative experience in middle school, and how Reito's actions are helping her expand her comfort zone. Reito, acknowledging his own tendency to help those in need, agrees to continue supporting Shion.
The school trip begins with a bus ride to a mountain lodge. Reito, Shota, and Shion's group are seated together. During the bus journey, Reito and Shion exchange messages, with Shion expressing her gratitude for his presence.
Upon arrival at the lodge, the students engage in various activities. During an adventure course, Shion reveals a fear of heights. Reito offers her encouragement and support as she navigates a challenging cliff descent. Later, during lunch, Reito and Shion find themselves eating together. Reito, observing Shion's animated discussion about her friends, suggests that she try facing him when talking about things she loves, as it seems to help her overcome her shyness. Shion agrees to try.
The next evening, Shion seeks out Reito again, confessing her feelings of being constantly helped and her desire to be more independent. She asks for his help in overcoming her anxieties. Reito, in turn, expresses his enjoyment of their current interactions and his own nature to help those in need, offering his continued support.
During the second day of the trip, the group participates in a "Truth or Dare" style Uno game, where the loser must reveal a person they are interested in. Sakashita, a popular boy in Reito's room, confesses his feelings for Tachibana, a girl in Shion's room. This event, orchestrated partly by Reito, seems to alleviate the tension in Shion's room.
Later, Shion again seeks Reito out, revealing that her fear extends to some girls as well, and that Tachibana likes Sakashita, who in turn is interested in Shion. Reito advises her to observe the situation and seek help from Haruno or Rin if needed. Shion, however, asks if Reito can help her, a request that momentarily stuns him.
The narrative concludes with Reito reflecting on the positive changes in his school life since meeting Shion and her friends. He acknowledges his own desire to help others and reaffirms his commitment to supporting Shion. The chapters end with the characters navigating their developing relationships and personal challenges.