"After School Dice Club" centers on the lives of three high school girls who form an unlikely friendship through their shared interest in board games. Miki Takekasa, a reserved and studious girl, finds herself drawn into the world of tabletop gaming after meeting Aya Takayashiki, a cheerful and outgoing transfer student, and Midori Ono, a quiet and mysterious classmate. The trio discovers a small board game shop run by a kind shopkeeper, who introduces them to a variety of games, each serving as a catalyst for personal growth and bonding.

The narrative unfolds episodically, with each chapter or episode focusing on a specific board game that mirrors the characters' struggles, aspirations, or relationships. Through games like "Catan," "Splendor," and "Love Letter," the girls explore themes of strategy, cooperation, and competition, while also confronting their own insecurities and fears. Miki, initially hesitant and rule-bound, learns to embrace spontaneity and creativity. Aya, despite her bubbly exterior, grapples with feelings of loneliness and the pressure to fit in. Midori, who harbors a deep love for storytelling, finds solace in the imaginative worlds of board games, which help her connect with others.

The series also introduces secondary characters, such as fellow students and the shopkeeper, who provide additional perspectives and challenges. The games themselves are often used as metaphors for life, encouraging the characters to reflect on their decisions and relationships. The story balances lighthearted moments with deeper emotional undertones, creating a narrative that is both entertaining and thought-provoking.

"After School Dice Club" emphasizes the importance of friendship, communication, and self-discovery, using the medium of board games to explore these themes in a relatable and engaging manner. The series appeals to fans of slice-of-life stories and those interested in the growing popularity of tabletop gaming culture.