A new transfer student named Miyuki Hoshizora encounters a Märchenland pixie named Candy while on her way for her first day at school, noticing Candy left a pink book behind. At school, Miyuki struggles while introducing herself to her class when her classmate Akane Hino helps her break the ice. While checking out the library after class, Miyuki stumbles across a portal that takes her to a magical library. And then, in another part of town, Candy is being chased by an anthropomorphic wolf named Wolfrun. As a commander from the Bad End Kingdom, Wolfrun uses his powers to make the nearby townsfolk fall in despair while revealing his intention to gather an ideal amount of negative energy from humans to resurrect his master, Pierrot. When Miyuki risks her life to protect Candy from Wolfrun, she receives a magic compact called a Smile Pact that transforms her into the magical warrior Cure Happy. Wolfrun responds by creating a monster called an Akanbe, with Miyuki eventually getting the hang of her powers to destroy it while gaining a Cure Décor from the monster's remains.