Bat, the titular protagonist of A Boy Called Bat, is a dynamic character who experiences a transformation that leads him to self-acceptance and friendship. Bat is characterized as having autism spectrum disorder (ASD). His ASD, which is not explicitly stated in the book itself, is characterized through Bat’s difficulties with reading social cues, communication differences, sensory sensitivities, and special interests. While his core characteristics remain, Bat experiences a significant shift in his abilities to manage stressful situations and communicate, which helps him form connections.

Early on, Bat’s temper flares when he is faced with challenging situations, such as when the family runs out of vanilla and lemon yogurt, or when Janie physically stands in his way. Bat learns to be careful and control his anger around skunk kit Thor, and this practice bleeds into other interactions and alleviates his bursts of frustration and anger. He realizes he has his own ways of communicating. He is guided by his mother, Valerie—who warns Bat to adjust his behavior and suggests that Bat look into people’s eyes to learn about them—and Mr. Grayson, who challenges Bat in a safe and supportive environment. Furthermore, Bat learns to consider the needs of others by caring for Thor.