The boy is the master of black and white, while the heroine was traded by her parents and turned into a murder tool. She was raised and trained in a drug camp since she was a child. Although the records of her childhood are fragmented, she still remembers the decoding program taught to her by her grandfather. Why did that group of people insist on choosing her to train as a killer? Why was the boss tolerant and protective of her? To steal the male protagonist's USB flash drive and kill the male protagonist? For such an important task, there are obviously so many people with better qualifications than her, why is she doing it? All kinds of questions, is it you? Faced with the threat of the mission and the coming of love, where should they go...