He is a young boy of toddler's age who dies due to abuse from his mother's boyfriend. His mother had been half-asleep and gave the hungry Takeshi permission to eat pudding from the refrigerator. When her boyfriend later comes home, he reacts violently and unintentionally kills Takeshi. Takeshi does not die instantly, and his mother and her boyfriend leave him, believing him to be alive. Before his death, draws a fictional hero called "Muscle Rider", and when he awakes inside Gantz's room as a participant in the game he believes that Kaze is "Muscle Rider". Kaze watches over Takeshi during his first mission, and Kaze later decides to let him stay with him after learning of Takeshi's cause of death. Takeshi continues to believe that Kaze is Muscle Rider. By chapter 240, he discovers and uses the abilities of the suit, including the utilization of the "back attack", Kaze's signature move. Despite Takeshi's small size, he is capable of defending himself against average opponents. Having imitated Kaze's fighting style, Takeshi manages to dispel a group of monsters that surround him, as well as injure a rather large creature that comes from the river, earning himself 26 points at the end of the mission. He later even lands a surprise attack on the Gantz veteran, Nishi.