Doronpa hails from Texas, USA, initially dwelling in a squire's house before relocating to Japan, where he now shares a home with a human named Kaminari. His light pink form features properly divided legs and a large, detachable red star prominently positioned on his stomach; this star fuels his Obake powers. Beneath it, a Star and Stripes motif signifies his American origins.

He exhibits notable intelligence and proficient motor skills, coupled with the ability to transform into various objects and people. Doronpa's personality blends a tendency to annoy and mock the ghost Q-Taro with an underlying kindness and occasional loneliness, explaining his bond with Kaminari. This rivalry stems from both U-ko's admiration for Doronpa's intelligence and Doronpa's own enjoyment of provoking Q-Taro.

Despite their antagonism, Doronpa has impersonated Q-Taro during the latter's visits to the Obake world, preserving the illusion of Q-Taro's presence while causing mischief. Doronpa holds affection for P-ko, though his attempts to interact with her are frequently interrupted by Q-Taro. Hamburgers are his preferred food. His documented birth date is March 27th.