Shiki is suffering at the hands of her violent husband. The only time she can feel at ease is at the movie theater, while he’s away at work. On one of her regular visits to the theater, she meets a young man. And that encounter leads to a plan to kill her husband…?!

Xi Wu, a rebellious young mermaid, goes ashore to terminate her betrothal to the "fiancé" that runs a fashion store, but she ends up releasing the magical creatures sealed inside the mysterious dresses.

High school second-year Sakagami Sojiro is late for school one day, when he is given a ride by a mysterious girl who looks like a third-year, and claims that her fortunes are 100% accurate. She declares that he is fated to be with a girl younger than him... but little does he know that she's referring to herself! So begins a comedy of love between the fumbling Mizuki-"senpai" and clueless Sakagami!