Masuo Tōyama, who is known by the nickname Thomas, is presented as a dull and unemployed man. His background is that of an ordinary individual struggling to find stable work. His personality is described as unremarkable and somewhat listless, with a latent tendency toward perverse behavior. His primary motivation emerges when he encounters Ayane Tachibana, a woman he finds attractive, on a crowded train. The stimulus of her scent triggers an impulsive act of touching her hip, which marks the beginning of his predatory activities. He later receives instruction from an unnamed man who imparts an ancient technique for seducing and pleasuring women. Mastery of this skill becomes his driving force, and he travels to various locations to sexually gratify women. His role in the story is that of the central character whose actions drive the plot. Key relationships include Ayane Tachibana as the first object of his fixation and the mysterious man who acts as a mentor, granting him the ability that defines his later exploits. Over the course of the narrative, he develops from a directionless, uninspired individual into a confident and practiced molester who actively seeks out new opportunities. His notable ability is the learned technique, which he uses to give women sexual pleasure and to control encounters. The story does not explore any deeper psychological evolution or redemptive arc; his development is limited to the refinement and application of this skill.