Weak, clumsy, and shy, Tsukushi Tsukamoto is a prime target for bullies. Though he suffers through their torment, it leads to a fateful encounter with fellow Seiseki High School student Jin Kazama, a genius soccer player of the same age. After saving Tsukamoto from the bullies, Kazama invites him to a futsal match since his team is one man short.

Although he struggles to keep up with the more experienced players, Tsukamoto is passionate and persistent; not even an injured foot stops him from running around the field. His endless runs and continuous efforts inspire the team, particularly the unmotivated Kazama. As Tsukamoto scores the winning goal, he realizes that he thoroughly enjoys soccer, as well as playing alongside Kazama.

Inspired by Kazama, Tsukamoto decides to join him in the school's soccer club. Little does he know, the Seiseki team is renowned nationwide, and a terrible player like him might not even pass the selection process, let alone play in the first team. Even so, Tsukamoto forces his way into Seiseki with the only thing he is good at—running straight ahead!

Days was published digitally in English by Kodansha USA from April 25, 2017 to July 23, 2024.