Takako is a young woman living in Tokyo whose life derails after an abrupt breakup with her coworker. Dealing with depression, she quits her job and spends her days oversleeping in her apartment to avoid her feelings. She temporarily relocates to a room above her uncle's second-hand bookshop in the Jimbocho neighborhood, where she slowly discovers a love of reading.

Satoru is Takako's uncle and the proprietor of the Morisaki Bookshop in Jimbocho. He inherited the store from his father after spending his youth traveling the world to find where he belonged. He maintains a breezy, slightly unconventional demeanor that initially confuses his niece, but he offers her a patient environment to heal.

Momoko is Satoru's wife who abruptly left him years prior with only a brief note. She later reappears at the bookshop and moves back into the upstairs room without explaining her actions. She is extroverted and cheerful, though she remains highly evasive whenever anyone asks about her sudden departure or her current plans.

Wada is a young man who frequently visits the Morisaki Bookshop and the nearby cafe. He connects with Takako over a shared interest in reading, particularly discussing the tragic novel *Up the Hill*. He spends much of his time waiting at the cafe, hoping his recent ex-girlfriend will return to him.

Hideaki is Takako's former boyfriend who ends their relationship casually, expecting them to remain friends despite his impending marriage. He is largely inattentive to Takako's emotional distress. He refuses to take responsibility for the pain his actions cause, acting as though his behavior is entirely normal.

Sabu is an older, talkative regular customer at the Morisaki Bookshop. He visits the store primarily for conversation and companionship rather than just buying texts. He is fiercely protective of Satoru and highly critical of young people who do not appreciate classic Japanese literature.

Tomo is a waitress at Saveur and a graduate student studying literature. She is quiet but deeply passionate about books and authors. She becomes one of Takako's first friends in the Jimbocho neighborhood, inviting her to local events like the used book festival.

Takano is a young kitchen worker at the Saveur coffee shop. He is knowledgeable about foreign literature and openly infatuated with his coworker Tomo. He recruits Takako to help him learn more about Tomo's interests so he can pursue a relationship with her.

Haru is an employee at the high-altitude mountain inn where Momoko and Takako stay during their hiking trip. She remembers Momoko from years prior, noting a positive change in her demeanor during the current visit.