A legendary assassin found the light of life. It was an underground idol! Endo Owaru is the best hitmen in the Fujiyama Group, a huge black market organization. He was feared as a "killing machine" because of his ruthless work and overwhelming fighting power, but one day he decides to retire. The reason for his decision was to live his life proudly with Kaorin of the underground idol Rosaceae. Can a man covered in blood and sorrow protect the light of life that he has finally obtained?!