Barom One emerges from the fusion of childhood friends Takeshi Kido and Kentaro Shiratori, born on the same day. Their physical union activates a transformation via extraterrestrial Kopu's device, merging bodies and consciousness into a single superhuman entity to confront cosmic threats from Doruge and its minions. Within this merged form, Takeshi and Kentaro retain distinct consciousnesses while inhabiting a shared body. Their presence manifests as miniature figures visible within Barom One's eyes during fusion, enabling joint control. Takeshi contributes raw physical strength and courage, while Kentaro supplies strategic intellect and analysis—a synergistic dynamic vital for combat effectiveness. Barom One wields enhanced physical capabilities including superhuman strength, durability, and combat proficiency. The entity employs specialized gear such as the Machroad, a transforming vehicle serving as both transport and weapon. Additional tools include Kopu-provided interdimensional threat countermeasures and a radar system tracking Doruge's monsters. This fused warrior primarily battles Doruge's evolving minions, the "Majin." These adversaries initially mimicked animals or plants but progressed into anatomical horrors: Kuchibiruge (mouth-headed), Hyakumeruge (eye-clustered), Nougeruge (brain-themed), and Udegeruge (giant-handed). Barom One engages them in tactical confrontations, typically culminating in explosive defeats. No evolution occurs in Barom One's core nature, fusion mechanics, or objectives across the manga (1970-1971), tokusatsu series (1972), or anime adaptation (2002-2003). The character lacks independent personality, existing solely as an expression of Takeshi and Kentaro’s combined will and cooperation, with no autonomous thoughts or motivations beyond their fused consciousness.