When Ao Hoshino discovered that his parents' laboratory notes contained blueprints for a sonic weapon named after him, the holographic engagement announcement on the top floor of the Kujo Group Building had woven a paradox between his fate and the consortium's daughter, Ruri Kujo. In order to decipher the truth about the "Devil Scale" left behind by his mother, he had to find a balance between the system prompts and the heartbeat rate - every time he said "I love you" to Liuli, the power of the weapon would be weakened, and the real killer move turned out to be the "Gothenburg Variations" that the girl unconsciously hummed when she was suffering from crystallization disease.
In this death performance with Tokyo as the key, Hoshino Ao must reorganize the "Rainbow Gear" band that has disappeared for ten years, and use musical equations to fight against the quantum system that controls human talents. When the system's forged heartbeat frequency collides with the fatal crystallized resonance of the consortium's daughter, they gradually discover that the most dangerous resonance is that when the mother put the baby Liuli into the sonic chamber twenty years ago, the two souls destined to kill each other had already composed a fugue of love.
