In tales of individuals who swap bodies, they invariably return to their original forms. But what if that never occurs? Regrettably, this is the precise dilemma Yui Ootsuka and Yuuta Kimura face. One day, after Yuuta crashes down on Yui from the treetops, both children find themselves inhabiting unfamiliar bodies. Yet, no matter how desperately they attempt, they cannot restore things to their original state. Ultimately, they decide to live each other's lives as if nothing had transpired, resolved to keep the incident secret. Although they were merely classmates before, this inexplicable accident binds their fates tightly together. For years, Yui and Yuuta struggle through a life that is not their own. In this exhausting situation, the two of them discover what it truly means to walk in someone else's shoes.