In a time of extremely low birth rates, the government develops a matching program that calculates compatibility based on DNA and personality. A 100% match is exceptionally rare and can even enable pregnancy between same-sex couples.Yoon Heewon and Seo Hyunsoo are rival team leaders who have competed since their university days. But when the matching program suddenly announces in front of their coworkers that they are a 100% match, everything changes. What Heewon doesn’t know is that Hyunsoo has secretly been in love with him for ten years. As the two become increasingly entangled because of their perfect compatibility, Hyunsoo begins to wonder whether he can really put an end to his longtime unrequited love. +