Kazuki Hongo is a third-year student and member of the Yokohama Minato badminton team, graduating upon the conclusion of his involvement. He actively competes in tournaments as part of the team.

During the First Arc Placing Matches, Hongo battles in singles, notably securing a 13-11 victory against Yu Tanaka. He also partners with Takuya Yoshimura in a doubles match against the Higashiyama twins, Taichi and Yoji; the specific score remains undocumented.

In the Interscholastic Prefectural Tournament Squad Event, Hongo faces Kyohei Honma from Hojo in a demanding singles match. The contest stretches to three games, with Hongo ultimately winning (21-14, 18-21, 21-16).