Maho is a young boy from a remote mountain village who appears in the story of the mushi known as Ah. He is the grandson of Shirasawa, the village headwoman. His mother, Matsu, suffered from the same unusual condition and has since passed away, and his father is also deceased. Maho is a child consumed by grief following his mother's death. In his sorrow, he began covering his ears, mimicking his mother's behavior before she died. This act of mourning and withdrawal inadvertently allowed a species of mushi called Ah to infiltrate his body. As a result, he grew four soft horns on his forehead. The horns do not cause physical pain but severely affect his hearing, amplifying the normally inaudible sounds of mushi to an overwhelming and incessant roar that weakens him over time. His primary motivation is simply to find relief from the constant, draining noise that plagues him, a wish that ties directly to his mother's final desire to sleep in a place of complete silence.

Within the story, Maho serves as the central figure afflicted by a mushi-related illness that the protagonist, Ginko, is called upon to investigate and treat. His role is that of a patient whose condition is both physical and deeply emotional. His key relationship is with his grandmother, Shirasawa, who cares for him and seeks Ginko's help out of concern for his deteriorating health. His relationship with his deceased mother is the emotional core of his affliction; his actions are a response to her death, and her final words to him, which he cannot remember due to the noise, hold the key to his recovery. His interaction with Ginko is that of a caregiver and guide. Ginko does not simply cure him but creates a quiet space with his mushi tobacco smoke so they can communicate, ultimately helping Maho understand the nature of the sound within his own body.

Maho undergoes significant development from a passive sufferer to an active participant in his own recovery. Initially, he is shown sneaking away from home, overwhelmed and seeking any refuge from the noise. After Ginko demonstrates the truth about the sounds of living things, Maho courageously covers his own ears, facing the very gesture that began his affliction. This act allows the Ah to be destroyed and his horns to fall off, representing the resolution of his grief. His notable ability, born from his infection, is his heightened perception of mushi sounds. The horns on his head act as amplifiers, granting him access to an auditory world that normal humans cannot perceive, though this ability is a curse that slowly drains his life force rather than a useful skill.