A woman finds a strange animal in the rain. It offers her an umbrella to show its charm. Impressed by its wit, she takes the dog-like being home, beginning their shared story.

Miya lives with her fearsome stepmother and her two daughters, and is resigned to a miserable life at their hands. However, they are actually kind and sweet to her, and a comedy of errors sets off.

Mysterious creatures have been terrorizing an island, forcing locals to flee their once-thriving home. With government funds lacking for monster eradication, Tajima purchases the only construction company left and transforms it for the task. Thankfully, the brilliant Testuro Okino and his new robot, Bullbuster, come to their aid. But the team is on a tight budget. Can they save the island?