Hayato Hiiragi and Tsukasa Terada, former childhood friends and current neighbors, still spend time together but Hayato avoids meeting Tsukasa's gaze. Tsukasa is unsure of the reason for the change, but he can tell that Hayato only maintains eye contact with a select few and for no longer than five seconds with others. The truth behind this is that Hayato has the power to copy anyone's sexual desires by locking eyes with them for five seconds. He then experiences the same pleasure they receive from intimate acts for 24 hours, but can only achieve release through this means. Hayato can copy the desires of anyone, including men, women, and animals, but has made a vow to never use this power on Tsukasa, except for one incident in their past. However, one day, Hayato accidentally locks eyes with a stray cat in a mirror and she goes into heat, and the first person Hayato accosts is Tsukasa, overwhelmed by the desire to be impregnated.
