Hoshino Yu died in a car accident, and Hoshino Haru felt that the sky was falling.
The Hoshino family moved away from that sad place. There was a pair of brothers next to their new home. The elder brother, Ichijoji Tomo, was as old as Hoshino Yu.
When he first entered elementary school, Tomoya Ichijoji died in a car accident, but Ken Ichijoji paranoidly believed that he had killed his brother.
When Hoshino Haru was in second grade, she was invited by her brother's friend, Taichi Yagami, to go to the summer camp and go on a fantasy trip.
Three years later, Tyrannosaurus Transformers appeared in the Digimon world, and new chosen children appeared.
But there is also a selected child beside the Tyrannosaurus Transformer, who has saved the Tyrannosaurus Transformer from fire and water several times.
Concept: The story of childhood sweethearts Ken Ichijoji and Haru Hoshino