The boy was out of school and had nowhere to go and came to Rainbow City to seek refuge with his only sister. In Rainbow City, he faced a society where the jungle prevailed, and the weak had to seek shelter. Therefore, he joined an organization led by a girl named Qiuzi, which is an organization marked by blue.
The young man did not know that Qiuzi was already preparing for war because of his appearance. When the carefree young man noticed something strange, the war had already broken out. When he learned that the fuse of the conspiracy was himself, he decided to leave in order not to cause trouble to others. Just before he left, Qiuzi's words seemed to make him understand something. Whether to follow Qiuzi into the battle or to leave, and what trend his decision would bring to the war situation...