The provided chapters introduce Kazahana, a high school student who lives with her distant father and mother, and her younger sister, Yumemi. Kazahana is a diligent and capable student, excelling in academics and sports, but struggles with emotional connection due to her family's lack of affection. Her father is often preoccupied and her mother is emotionally detached. Yumemi, on the other hand, is timid, clumsy, and appears to be the target of bullying.
The narrative begins with Kazahana's morning routine, highlighting the quiet, almost detached atmosphere of her home. She observes Yumemi's struggle with simple tasks and her fear of her older sister, a stark contrast to the happy family Kazahana draws in her sketchbook, a reflection of her unfulfilled desires.
At school, Kazahana's academic and athletic prowess is evident, earning her admiration but also a sense of isolation. She politely deflects requests for help with studies, admitting her difficulty in teaching others. She also encounters Izumi Ryo, a boisterous classmate who tries to engage her, but Kazahana maintains her distance.
A significant turning point occurs when Kazahana and Yumemi are walking home. They witness Yumemi being bullied by a group of girls who mock her for her perceived incompetence and her sister's superior abilities. Kazahana, despite her initial fear and desire to flee, intervenes forcefully, using her past academic achievements as leverage to protect Yumemi. This confrontation marks a shift in Kazahana's behavior, as she actively defends her sister.
The narrative then flashes back to a childhood incident where Kazahana and Yumemi found a stray kitten. Kazahana, though initially reluctant due to their family's financial struggles, ultimately helps Yumemi care for the kitten. However, their efforts to find a home for it end tragically when the kitten is run over by a car, an event that deeply traumatizes both sisters and leads to them burying it together. This flashback reveals a shared trauma and a nascent bond between them.
Following the bullying incident, Kazahana and Yumemi walk home in silence, a reflection of their strained relationship. Another flashback details a painful memory from their childhood where Kazahana, seeking her parents' affection, deliberately performed poorly on a test, only to be met with anger from her father and indifference from her mother. This reinforces Kazahana's feeling of being an outsider in her own family.
The story then takes a dark turn. During dinner, Kazahana and Yumemi realize they have been drugged. Their parents, with tearful apologies, reveal they are "no longer good" and that Kazahana and Yumemi are "different." Kazahana's father takes Yumemi, and her mother follows, leaving Kazahana alone. She wakes up to find her aunt, uncle, and police present. Her parents died in a car crash, a presumed suicide. Kazahana learns that her father was in debt and that she was considered the "successful" one, unlike her parents and Yumemi.
Kazahana is taken in by her uncle and aunt, who have no children and see her intelligence as a positive trait. She visits Yumemi in the hospital, who has suffered severe injuries, including the loss of sight in one eye and paralysis in her legs. Yumemi struggles to communicate, but Kazahana understands her unspoken needs. The narrative highlights Kazahana's deep-seated loneliness and her struggle to connect, even as she cares for Yumemi.
A subsequent flashback reveals Kazahana's deep envy of Yumemi's closeness with their father, leading her to intentionally fail a test to gain attention, which backfires.
Later, Kazahana, now attending a new high school, continues to visit Yumemi. She reflects on her family's tragic fate and her own feelings of abandonment. She realizes her own actions, particularly her plea to Yumemi not to leave her, were as much about her own fear of being alone as about protecting Yumemi. The story ends with Kazahana embracing Yumemi, finding solace in their shared reliance on each other, while Yumemi, in her own way, reciprocates the sentiment, acknowledging Kazahana as her only remaining connection.
