An ordinary student named Seiji Aino was leading a dull life until a peculiar girl named Guri came to his doorstep. She claimed that she would die if Seiji did not kiss anyone. At first, Seiji thought it was just a religious soliciting scheme and walked away. But he was surprised when Guri passed through his door!
Guri held a magical notebook called the "Kiss Note" that could instantly make two individuals fall in love if their names were inscribed in it. As a cupid, Guri's responsibility was to connect couples. However, she mistakenly wrote Seiji's name in the book, compelling him to find someone to kiss.
Seiji was bewildered by Guri's bizarre tale, but he took a chance and kissed the school's most popular girl, Akane Hiyama – whom he had a crush on. However, Akane's emotions for Seiji surpassed the usual limits, and she became obsessive about him. As if that wasn't enough, Guri disclosed that she also had feelings for Seiji, sparking the beginning of his chaotic and comical love life. Would either of the girls be able to win Seiji over, or would unforeseen obstacles threaten to derail their aspirations?