Ponchi serves as one of the Guardian Ghosts for shaman Tamamura Tamao. This tanuki spirit, alongside kitsune spirit Conchi, forms a duo of 400-year-old animal spirits elevated to Seirei Class. Memorial statues of them reside in the Asakura Family's ascetic hall. Both spirits exhibit perverted and crude conduct, frequently neglecting their duties as house spirits. Their antics involve threats to publicly disrobe or urinate on opponents, utilizing Ponchi's oversized testicles as restraints. Despite being nuisances, they remain unsealed due to practical reconnaissance utility—typically involving voyeurism—performing basic divinations rooted in undue suspicion, and casting minor curses amounting to harassment. They initially refused clothing until Matamune forced them into cloth diapers. Kyōyama Anna later reinstated this attire after disciplining them for peeping at women's baths, as they deeply fear her intimidating presence. Ponchi’s documented hobbies include stealing underwear, with chocolate noted as his preferred food. In character popularity polls, Ponchi and Conchi jointly ranked #30 in the first poll, while Ponchi individually placed #60 in the second.

Ponchi engages in combat via Oversouls formed with Tamao. In the weapon-type Oversoul "Angel," Tamao integrates Ponchi with a planchette medium to create a large heart-shaped shield sprouting Ponchi’s legs at its apex. Its primary technique, "Tan-Tan-Tanuki's Thousand Tatami Mats," is a defensive maneuver with offensive applications: it expands Ponchi’s scrotum from the shield to envelop opponents, trapping them while also shielding against explosions and cushioning falls. This contrasts Conchi’s "Cupid" Oversoul, which forms a bow and arrow. Media adaptations diverge: the 2001 anime depicted Ponchi and Conchi with childlike tendencies, seeking comfort from Tamao when injured. For international releases, the English manga redrew Ponchi’s prominent testicles as a "large belly," though the 2021 anime retained the original design. Their names derive from Japanese onomatopoeia—"Pon" echoes a tanuki drumming its belly, while "Kon" mimics a fox’s bark. Design-wise, Ponchi draws inspiration from Stimpy of "The Ren & Stimpy Show," with Conchi paralleling Ren.

Character development occurs in the sequel "The Funbari Onsen Saga," where Ponchi and Conchi display more civilized behavior. They appear in kimonos, with Ponchi adopting a pipe-smoking habit and Conchi growing long black hair, contrasting earlier depictions and indicating adaptation over time.