Datto is a ghost who was killed in a car accident and helped Keiichirou in training for race. Since he died by being hit by a car while he was training to win the race game of the sports festival, he slashes off and gathers legs of sprint runners. In the end of episode 5 he was about to slice Keiichirou's legs off with a scythe, but instead he stopped the scythe when it was about to hit him because of what Keiichirou said about who he wants to winning the race for Datto's dead friend (who is in fact was Datto) and the words of Satsuki that Keiichiro believed him to be a friend. After that, Datto was put into spiritual sleep after he blocked the scythe. In the end of the episode Keiichirou tosses the medal he won to the sky for Datto.
This ghost has two distinct personalities: one is of a boy who runs barefoot at incredible speed, while the other is a diabolic hare-like scythe demon.