Until Your Sword Breaks summary: In the Edo Era! Tsukimiya Matsuri, a beautiful girl who is admired by everyone, is facing a big problem... The man she loves, Tsukimiya Yonosuke, is not interested in her. She confesses her love to him in a very mature way, but he doesn't take her seriously... because they have grown up together since they were children and are like a family! Matsuri has placed herself too much as "part of his family"! It's a shame... Matsuri-chan! But Matsuri has a reason for wanting to change Yonosuke. In exchange for his life, Yonosuke wants revenge on the general who killed his former love. Seeing him use his entire life for reckless revenge, Matsuri decides.... "I will be his reason for living." To get him off the path of revenge, she wants to fill his head with herself so that he can forget his revenge. Even if the other party thinks of her as "family," the dedicated and healthy Matsuri will not be defeated! The beginning of a courageous action-comedy Edo Era love story! Hang in there, Matsuri-chan!