Botan Kamiina is a twenty-year-old university student starting her new life in Chichibu, Saitama Prefecture. A newcomer to alcohol, she becomes curious after encountering her dormitory's quiet and reserved leader, Ibuki Tonami, who is secretly a connoisseur of spirits. Despite being of legal drinking age, Ibuki is self-conscious about the hiccups she gets when she drinks, leading her to avoid public drinking. Their meeting leads to Botan's first taste of a highball, forging an unexpected bond between them as they become private drinking partners. As a novice, Botan begins exploring a wide world of alcoholic beverages, from Japanese sake and shochu to whiskey and wine, while her true personality emerges when she is intoxicated: she becomes bold, surprisingly flirtatious, and speaks her unfiltered mind.

The series is set against the backdrop of university dormitory life, where the shared experience of drinking serves as a catalyst for deepening relationships and personal discovery. Beyond simply consuming alcohol, the narrative incorporates how these experiences intersect with other cultural elements like music and film, which the characters enjoy alongside their drinks.

The core of the story focuses on the evolving relationship between Botan and Ibuki. While Ibuki is initially hesitant, she finds a non-judgmental companion in Botan, who accepts her quirks without question. Their friendship is observed and influenced by a cast of fellow students. Kanade Gujo, a graduate student, harbors romantic feelings for Ibuki and is initially disheartened to see her growing so close to Botan. Yaeka Kitamori, a second-year student with a love for the outdoors, and Akane Yusa, a guitarist in a band, form another close pair of friends within the group. The circle also includes Zhang Jinglan, an exchange student from Taiwan who develops her own complicated feelings for Kanade.

The narrative arcs follow Botan's gradual education in drinking etiquette and taste, from her first hesitant sip to confidently navigating different social situations involving alcohol. A significant recurring element is the contrast between Botan's sober, polite demeanor and her uninhibited, charmingly aggressive drunken personality, which leads to awkward, humorous, and heartfelt confessions that slowly blur the lines of their friendship. The story explores the vulnerabilities that emerge when inhibitions are lowered, creating a space for honest communication and the slow blossoming of romantic tension, particularly between Botan and Ibuki, as well as the unrequited feelings within the larger friend group.