Pi-chan is a Goddess of Sexual Love dispatched from heaven to help Natsu Andou, a 30-year-old virgin librarian, build relationships and lose her virginity. She typically appears in Gothic Lolita fashion alongside her twin sister Kuu-chan, distinguished by her pink hair and orange eyes.

As the more proactive and assertive twin, Pi-chan frequently pressures Natsu to pursue romance. She exhibits expressive behaviors ranging from aggressive encouragement to moments of genuine care, especially concerning her past acquaintance, the deity Daigorou. Her determination to protect Natsu leads her to adopt disguises, including cross-dressing as a boy to pose as her brother and thwart Daigorou's schemes.

Pi-chan's contentious history with Daigorou dates back to elementary school, where he often flipped her skirt. Despite constant arguments, she harbors romantic feelings for him and believes they are mutual, though Daigorou rarely acknowledges them. Their relationship shifts significantly when Pi-chan seeks Daigorou's help to reconcile Natsu and Hayao Imagawa. During a private talk at Hayao's apartment, their mutual attraction leads to a romantic encounter, establishing them as a couple.

Pi-chan remains committed to her mission, coordinating with other deities to engineer a reunion between Natsu and Hayao after a conflict, demonstrating her ongoing investment in facilitating human relationships alongside her own romantic developments.