A Tiring Spell Is a Trip to the Beach/Love's Spell Is a Trip to the Beach - S1.E5

A. When a typhoon ruins their day at the beach, the girls try to improvise at the nearest hotel.

B. Following an accident with their floats, the girls are saved from drowning by Lulu, a mermaid who is the princess of the merfolk. They soon help her in obtaining a boy that she has a crush on, who Yuma ends up take. Lulu finds a mate in a jellyfish and, at the end of the episode, Yuma and the other nether princess have a fight. The girls (excluding Yuma)go home, while Yuma and the boy go for a swim, the boy turns out to be a spirit leading Yuma to her doom.