Originating from Japanese folklore as the fisherman who rescued a turtle and visited the underwater Dragon Palace, Tarō Urashima appears in the *Dr. Slump* universe exclusively within the film *Dr. Slump and Arale-chan: Hoyoyo!! Follow the Rescued Shark...*. Here, his design and role incorporate parody and adaptation. He encounters Arale Norimaki and her family after their invitation to the Underwater Kingdom. Visually distinct from traditional depictions, this version sports the attire of a Wild West prospector, reflecting Akira Toriyama's cultural reinterpretation and humor; his design shares similarities with Master Roshi from *Dragon Ball*, as both draw from the same Urashima Tarō legend. During the film, Urashima joins Arale in activities at the underwater amusement park, engaging in playful interactions consistent with the series' comedic tone. His inclusion nods to the folktale's element where the protagonist receives a mysterious box after his adventure. This box is referenced elsewhere in the franchise, specifically in the series *The Birth of Arale!*, where Arale mentions saving Tarō Urashima during a time-travel incident and receiving a box that aged Senbei Norimaki when opened. His role across official Dr. Slump media remains confined to this cinematic appearance and the referenced anecdote, with no documented further development or appearances in other seasons, OVAs, or spin-offs.