After battling monsters all night, a sleepy Princess in Black decides that she needs a vacation. After all, the Goat Avenger, a new hero who looks oddly familiar, has offered to protect the goats while she takes a much needed break. The very next day Princess Magnolia rides her bicycle to the seaside, where the air is salty, the sun is shiny, and the sea is as blue as monster fur. But just as Princess Magnolia is about to take a nap on her hammock, she hears a "ROAR!" Seriously? A monster? On the perfect beach? Impossible! Could a sea monster really ruin this vacation for the Princess in Black?