Teacher Sun and Nuea, a couple with an age gap, have been living together peacefully—until a major problem arises: Sun starts experiencing erectile dysfunction and can no longer be physically intimate with Nuea. As tension builds in their relationship, Sun turns to "Third," the campus shaman, for help. He receives a mysterious bar of magical soap along with a strict warning: "Never use it with anyone else." But of course, chaos strikes— Nuea ends up joining Sun in a bubble bath filled with that very soap, and in a clumsy moment, their heads knock together... Boom. They switch bodies! Suddenly, Teacher Sun finds himself in the body of a university student, while Nuea wakes up as a respected adult educator. Their lives are turned upside down as they try to navigate each other's worlds, all while having no idea when—or if—they'll ever return to their original bodies.