The girl Miyo (voiced by Shida Mirai), nicknamed Infinity, never hides her affection for the boy Hinode (voiced by Hanae Natsuki). She obtained a mask that can turn into a cat at a festival, and used it to get close to Hinode. As the communication deepened, Miyo became more and more trapped in the state of contacting Hinode as a cat, and eventually could not turn back into a human. At this time, Hinode also discovered his feelings for Miyo. After discovering the truth, he embarked on an adventure to help Miyo turn from a cat back into a human.