Discovered by Shinnosuke Nohara lying on a road, Tanba appears as an elderly man. His true nature is the spirit inhabiting the legendary Golden Soul Hot Spring water. Grateful after Shinnosuke offers him a bath at the Nohara residence, Tanba places the source of this mystical hot spring beneath their house, directly linking their home to its power. Tanba commands absolute control over thermal energy, manifesting hot spring water anywhere through his fingertips. His connection to the hot spring's origin pulse remains vital to its existence. When the bath-hating organization YUZAME attacks, Tanba lends his power to the Nohara family, enabling their transformation into superpowered forms to combat YUZAME's giant robot. His history traces back thirty years to a critical incident where he unknowingly contributed to YUZAME leader Dr. Akamamire's trauma. Using the alias "Number 3" at the time, Tanba frequented public baths with Akamamire. Their association ended when Akamamire misplaced a locker key during an outing, triggering his lifelong aversion to bathing. Later, Tanba facilitates Akamamire's immersion in the Golden Soul Hot Spring. The waters' restorative properties heal this psychological wound, mending Akamamire's broken psyche. Tanba shares a physical resemblance to Kusatsu, captain of the hot spring-protecting G-Men organization. Following the climactic battle, Tanba resides within the hot springs that emerged during the conflict, maintaining his connection to the waters.