The astronomical event “Apple Moon” occurs once every 300 years. On that day, Sakuma, while visiting the ocean with his classmate to observe the event, ends up meeting a parasitic alien instead...?

They showed up out of nowhere. Graffiti that moved as if they were alive. People started calling them the "living pictures" and they started getting praised and sold for high prices. The origins are unknown and no one knows who said it first, but people say they are being created by someone named "Kilroy".

Enter Suzume, a young artist who aspires to create great art just like Kilroy but has been struggling to do so. One night, her everyday life takes a sudden turn as she comes across none other than Kilroy himself.