Ocean, Swimsuits, and Slaying Evil Gods!

 is the 4th episode of the Endro~! anime.

Summary
During summer break, the gang head to an island to investigate monsters as part of their summer homework while also enjoying beachtime. While fishing for food, the girls come across a mackerelman who had accidentally released an evil god that has enslaved his friends. Offering to help, the girls face off against the evil god, who is defeated by Yusha's Hero's Sword before being eaten by their mascot Chibi Dragon.