From MangaHelpers:
Gaie Kensei is just starting his high-school life, at the same school as his childhood friend Nireki Hikari. His high school boasts a highly competitive kendo club, and Kensei is excited to join and begin learning from the older students. However, the fact that Kensei's father is a legendary kendo competitor works against him. Once the other club members learn that Kensei is not as good as his father, they refuse to let him join the team.
Wandering around in despair, Kensei comes across the secret hideout of Ashihara Naoto. She seems highly skilled in kendo, though she spends all her time reading and claims she hates the sport. Naoto reluctantly helps him train up to prove his worth to the kendo club, though she refuses to join the club herself. On the final day of club sign-ups, Kensei finally makes it into the Kendo club, along with his childhood friend Hikari, who becomes the first female member! Their kendo-centric high-school life is only beginning.