P-ko is the younger sister of Q-taro, O-jiro, X-zō, and O-zetto, belonging to a ghost family from the Obake world. Her parents are X-zō (father) and O-zetto (mother).

Residing in the human world as part of her studies abroad from the Obake realm, she lives with Yukari Kawai, Shinichi Ohara's girlfriend. This places her within the extended social circle connected to the Ohara family, who host her brother Q-taro.

She displays notable intelligence and proficiency in gaming, yet struggles with domestic skills like cooking and sewing.

Physically, she possesses a white body and wears a distinctive yellow and red check-patterned skirt. Her appearance features a single prominent strand of head hair, and her height is comparable to her brother O-jiro.