Tarō Jirōmaru, a 31-year-old novelist, is a frequent lodger at the Kissuisō hot spring inn. He writes erotic novels, incorporating the personalities and interactions of the inn's staff and guests into his stories without their consent. His mounting unpaid lodging bills culminate in him confining Ohana Matsumae after she discovers his drafts during cleaning. This sparks a staff-wide chase when he attempts escape by stealing an inn vehicle, ending in his despairing leap off a seaside cliff. Rescued from drowning by Nako Oshimizu, he laments his lack of writing talent. Ohana confronts him, acknowledging his stories as perverse but admitting they revealed unrecognized aspects of herself. To settle his unpaid bills and damages, he begins working at Kissuisō. His presence serves as the primary source of comedic relief through eccentric behavior and observations about the staff. Ironically, he previously authored a cooking manga that inspired both Minko Tsurugi and Tōru Miyagishi to pursue careers as chefs. His inn duties involve menial tasks, and his outsider perspective often highlights the quirks of other characters. In later appearances, including the film "Home Sweet Home," his narrative function remains consistent, providing lighthearted moments without significant personal evolution beyond his initial integration into the inn's operations.