P-ko, a ghostly obake and central figure in the franchise, serves as the youngest sibling in a family comprising Q-taro, O-jiro, father X-zō, and mother O-zetto. Her appearance features a pale-white form, a solitary strand of hair, and a vibrant yellow-and-red checkered skirt, with stature matching her brother O-jiro. Balancing dual worlds, she attends school among humans while residing in the human realm with Yukari Kawai—roommate and girlfriend to Shin’ichi Ohara.

Renowned for sharp intellect and gaming prowess, P-ko contrasts these strengths with comedic ineptitude in household chores like cooking or sewing. Her aversion to confrontation leads her to lean on allies like Yukari during tense social encounters. Friendships span Shota Ohara, Shinichi Ohara, and Doronpa, an American obake smitten by her—though their rapport receives minimal elaboration.

Among her siblings, she shares a notably close, playful bond with Q-taro, reflecting familiar camaraderie over narrative-driven complexity. Across various media, her role persists as a steady comedic support within ensemble casts, anchoring lighthearted scenarios without undergoing transformative arcs or shifts in her established persona.