St. Valentine's Day..., Hikaru is an ordinary but kind student. He gets only two chocolates out of courtesy from Saki, his childhood friend, and Hotori, his older sister, every year. But he receives the chocolates from five girls this year, and he is forced to choose one girl out of them by White Day. Since then the five girls try to approach him in various ways, and their deeds gradually get bolder and bolder.... Who is Hikaru going to choose on White Day...?