A wandering apothecary of unknown origin, the Medicine Seller travels wherever rumors of the supernatural take root. Calm, observant, and unnervingly perceptive, he rarely reveals his true thoughts, instead speaking in measured riddles and quiet questions that often leave others more unsettled than reassured. Though he presents himself as a humble merchant carrying medicines and charms, his true purpose is to confront Mononoke—vengeful spirits born from powerful human emotions.

Unlike an ordinary exorcist, he cannot simply destroy a Mononoke. Before he can draw the sacred Exorcism Sword concealed within its sealed scabbard, he must uncover three truths: the Mononoke’s Form, its Truth, and its Reason. Only when these are revealed can the blade be unsheathed.

He possesses keen intuition, extensive knowledge of folklore, medicine, and the occult, and remains remarkably composed even in the presence of horrors that would break most people. Rather than rushing into conflict, he patiently observes those around him, believing that the greatest monsters often emerge from human hearts before they take spiritual form.

His age, origins, and even whether he is entirely human remain unknown. He rarely speaks about himself, avoids forming attachments, and disappears as quietly as he arrives once his work is complete. Despite his detached demeanor, he shows compassion toward those caught in tragedy, seeking not only to slay Mononoke, but to uncover the suffering that gave them life.