Kanako Ooba is a naive girl who works a menial, low-paying job. Hoping to make more money, she accepts the task of transporting an anonymous duo. Unbeknownst to her, the pair has stolen from a notorious yakuza group—resulting in the three being captured by the group members. Although Kanako always believed that she was living at rock bottom and would never escape it, this desperate situation makes her realize that she wants to live her life to the fullest. As Kanako is about to be buried alive, an unnamed buyer swoops in and saves her from certain death. When she awakens in a small restaurant named Canteen, her savior turns out to be Bonbello, the manager of the establishment that caters to a customer base of murderers. Since Bonbello desperately needs a new waitress after his old one was killed, Kanako becomes the ninth to work at his diner. While Bonbello is ruthlessly cold toward Kanako, the rotating cast of criminals is more than enough to keep her on her toes. With each customer she serves, she cannot help but see the small bits of humanity that remain in these murderers—especially when Bonbello's cooking can magically change the atmosphere. [Written by MAL Rewrite]

Diner won the Japan Adventure Fiction Association Grand Prize in 2009 and the Haruhiko Oyabu Award in 2011. A live-action film based on the series was released in Japan on July 5, 2019.