An odd murder case that only targets the person whose last name is "SATO" was happening in Japan. Meanwhile, high school student SATO Tsubasa winds up in a parallel world during a fight with gangster. Everything seemed the same, but his friends, classmates were somehow different from who they used to be. Tsubasa could not comprehend what was happening around him, but when he sees a girl getting killed in front of him by a persuer, he finds out that he is now in a world where the Lord of the land plays a fatal game of "tag". The real chasing game (ONIGOKKO) that targets people named "SATO". If you get clear away for few hours a day when the game is on going, and succeeds in running away for a week in total, any wish you have comes true. Tsubasa eventually notices that the parallel world is linked to the real world, killing same person who has already been killed in the parallel world. And when the siren sounds to signify that ONIGOKKO has begun, Tsubasa races to protect his sister who of course has the same last name.