Play a game with me―― If your heart pounds, then you lose the psychological warfare love comedy! ――The last day of the first semester. Being tired of everyday, and simply digesting each day, a high school student, Kashima Hayate receives a confession from the class idol, Fujinomiya Shirayuki. However, the next instant, Hayate is time-leaped to September 1st, from the beginning of summer vacation to when it had already ended! Shirayuki’s true identity is that of a ‘time thief’ who uses her good looks to deceive people and steals their ‘time’ with a mysterious hourglass. Hayate, who had his entire summer vacation stolen from him, decides to challenge her to a fierce psychological warfare to regain his ‘time’ of one month. If your heart pounds during your date, then you lose ‘time’ in the ‘time contest game’. ――This is the story of me, regaining my youth after the summer vacation of my first year at high school was stolen.