There's a Monster in My Opu

When a young boy heads to the beach to explore, a monster follows him and growls along the way. The boy surfs with his dad, chases sand crabs, and visits his auntie who lives by the sea. The monster follows the boy to Matsumoto's to get a shave ice treat. What happens when the boys slurps the shave ice to the cone? Read to the end to find out.