Seiji Honda lived with his mother Ikaeda and stepfather Noboru. Unable to speak, Seiji expressed himself primarily through his telekinetically-manipulated action figures, particularly a green, motorcycle-riding figure. He spent most of his days secretly using his abilities to stage epic battles between his action figures to distract himself from his somewhat unhappy real life, in which his stepfather regularly abused him and his mother.
For a long time, Seiji heeded his mother's warnings about not using his powers in front of Noboru, for fear that Noboru would have him sent away. However, one day Noboru found out, and prepared to send Seiji away. When his mother attempted to intervene, causing Noboru to threaten her life, Seiji launched an all-out war against Noboru, simultaneously animating every toy at his disposal and ordering them to attack Noboru.
The toys' assault greatly weakened Noboru, but he still pressed on, finally forcing Seiji to retreat onto the balcony of their apartment. Noboru made one final desperate leap for the boy, who fell from the balcony in an attempt to evade him. Noboru also fell with him, and was killed instantly. Seiji survived, but has been paralyzed since then, and his ability to manipulate action figures has truly become his only escape from his own life.