Rob is a young man who grows up as the only son in a big family. At the age of 13, he was kidnapped by a group "Shadow" and trained to be an assassin. Surviving the cruel training, he became the assistant of Alexander, the leader of one of the four units of Shadow. Pale, indifferent, and cold, Alexander is the best assassin in the group. With power in hand, why Alexander tears Shadow off and go South with Rob? What would happen during their adventure?