The concept is novel and the writing is warm. The heroine strays into a gang for her younger brother, and her ex-boyfriend in school dies as a result. In order to completely defeat the evil forces and stabilize the overall situation, the younger brother rescues his sister, and finally decides to join another, more powerful gang. Unexpectedly, the boss who makes everyone frightened is actually the childhood playmate who made an agreement with the heroine ten years ago, but he has lost his memory, which has caused unexpected consequences...