Urashima Eiji, a college student, goes to sleep after a fun drinking night with his friends. When he wakes up he discovers a beautiful girl next to him who treats him as if they are in a loving relationship. Later, Eiji finds out that 3 days have passed since he went out with his crew. What did he do during all that time and why does he have no memory of it? By confronting that reality, he will be caught in tragedy...

Hatori, a high school teacher leading an ordinary life, notices one day that his student, Spica Tsumugi, is being bullied. On a rainy day after school, Hatori finds himself alone with Tsumugi by chance.Hatori tells her, "I'll do something about it!" but Tsumugi gently takes his hand and says with a smile, "Hatori-sensei, you're such a liar."Teacher and student… two people who should not get too close. This somewhat bewitching girl will dramatically change Hatori's ordinary life.