Mai Sakakibara is heartbroken when her fiancé Ryouji dies in an accident. Now Ryouji had been involved in some genetics-related research. He told Mai that it was highly possible to have someone\'s baby simply by gathering DNA material such as saliva from a cigarette. Mai is inspired when she sees some of Ryouji\'s leftover cigarettes, and decides to try and have Ryouji\'s baby through genetical engineering. The problem is, Mai can\'t afford the procedure. Thus the company decides to recruit Mai as a DNA Hunter in order to help her earn the money she needs. A DNA Hunter is paid to collect DNA material (i.e. sperm) from a target that a client requests. The targets are usually highly capable, exceptionally skilled, and prominent men and female clients would use their sperm in order to have babies on their own. Mai agrees to be a DNA Hunter... and she is promptly sent off to her first mission... From Animetric.com