One year has passed since the death of Okita, a friend of Nucky and his friends. When they visit his grave in Osaka, Okita's father tells them about his childhood for the first time. He was a lonely boy who lost his mother to cancer at a very young age, and who was determined to live strongly on his own, so as not to bother his father, who was busy with work. This is the untold story of Okita Shigetoshi, who lived fiercely. The Gaiden is also included the Kodansha Manga Bunko volume 12 of Attention All Students