Tōdō-san acts as a catalyst for the protagonist's journey following their bar meeting. He possesses deep knowledge of spirits like rum and brandy, introducing the legendary Fake Denki Bran that sparks her quest. Black-haired with a mustache, stubble, and black eyes, he wears a distinctive green hat with a white center over a black suit and yellow dress shirt. Despite his intellectual engagement on alcohol, he attempts to grope the protagonist during their talk, leading her to punch him using the "Friendship Punch" technique learned from her mother. He identifies as a collector of erotic art and belongs to the Bedchamber Investigation Team, dedicated to preserving vintage erotic prints. This collection becomes central when targeted by the loan shark Rihaku for debt repayment. His strained relationship with his daughter, Naoko-san, stems partly from standing her up on an important occasion. This failure as a father weighs on him, and he expresses regret indirectly through advice about perseverance. When his erotic art collection is accidentally ruined during a confrontation with Rihaku, he attempts suicide by jumping from a building. His collecting group interrupts this act. The incident prompts an unexpected reunion with Naoko, who witnesses the event and acknowledges him as her father. During this encounter, Kosaka tries to court Naoko using rhetorical arguments, but she rejects his advances. Tōdō-san's narrative arc concludes with him joining the collective effort to support the protagonist during her drinking contest against Rihaku aboard the Three-Story Ferry. His presence during the subsequent celebrations indicates temporary integration into the broader community.