一弦定音！第二季

即将废社的时濑高中筝曲社。

来到只身一人的社长面前的是不良少年和他的朋友们，以及古筝的天才少女。

各自各自的古筝之乐所编奏的青春学园物语——

廃部寸前の時瀬高校箏曲部。一人になってしまった部長のもとを訪れたのは不良少年とその友達、そして箏の天才少女だった。それぞれの箏の音が紡ぐ青春学園物語―

The Tokise High School Koto Club has courageously pushed through their fractured and unsynchronized performance at the Kanto Region Traditional Japanese Music Festival. Clubmembers Chika Kudou, Satowa Houzuki, Takezou Kurata, Hiro Kurusu, Kouta Mizuhara, Saneyasu Adachi, and Michitaka Sakai are devastated to learn the negative results of their performance, leaving them crushed. Nonetheless, the group recognizes their potential and enthusiastically agree to collectively sharpen their skills, improve their flaws, and develop higher caliber playing to succeed in the upcoming national qualifiers in winter.

With the help of their now willing club advisor Suzuka Takinami, the group's goal gradually becomes achievable as they begin to grasp the foundations of good music and refine their koto-playing abilities, with the suggestion of performing more often to gain what they lack most—experience.

However, as their journey to nationals is underway, the koto club members face challenges that obstruct their focus and progress. Not only does the threat of other powerhouse schools and musicians remain, but the high school issues of budding romance and soon-to-be-graduating seniors also begin to push the limits of the determined group of teenagers and the future of the koto club.

[Written by MAL Rewrite]