Yuuto Amakawa is a normal high schooler with nothing special going on in his life. But when a strange girl visits him on his sixteenth birthday, everything takes a turn for the bizarre. Yuuto's in for a whirlwind of demons, cat girls, and magic galore!

Nothing more relaxing than hitting up the beach, right? Well, until the demons attack! After some adventures in shopping, Yuuto, Himari, and their classmates head to the beach. But under the sea lies a demon who seeks to kill Yuuto!

Another demon joins the crew as Shizuku makes the decision to live with Yuuto and the crew. While anguishing over the water demon's domestic skills, Himari gets a job at a local…maid café?! But there's more to the lead employee than meets the eye.