Kouha Mitsuha falls off a cliff, at which point she finds herself transported to some sort of medieval European fantasy world! While there, during a battle with some wolves that almost costs her her life, she realizes that she has the ability to come and go between Earth and this new world. Mitsuha decides to use this ability as much as she can. Why? To save up for retirement, of course! She sets her sights on saving eighty thousand gold coins--and this is the story of her schemes to get there!