Ichinose Ren, an elite businessman, is the envy of those around him, not only for his looks, but also for his spectacular sales performance. Surrounded by talented Alphas since his school days, Ren has always reigned supreme among them. He has always tried to be more Alpha than anyone else, hiding the fact that he is actually an Omega. However, the sudden death of his mother and the stress of being transferred to a quieter position within the company have caused him to become physically ill, and he discovers that he has contracted that 'D' disease that is horrible to even speak of. A love story connected from the past between Omega, who looks like Alpha, and Alpha, who can only see a Beta.