Satoshi Tanaka is a college student who just got granted an extended summer vacation. Coincidentally, an uncle he hadn't seen in some years makes him an invitation: to come enjoy summer at the Naval Treasure Resort with him. Excitedly, Satoshi accepts the invitation and takes the next train to the wonderful resort.
Bringing his gorgeous girlfriend, Maria Takizawa, along for the ride.
What he didn't know was that his uncle, Kendo Tanaka, used to be quite a lady killer in his days. A man full of virility and manliness, traits that had seemingly faded away in time.
But at the sight of Maria (or Mary, as her friends call her), that boundless virility of his youth comes back to him in a burst. And he finds no better use for it than to seduce any attractive young girl that may catch his attention... including the charming Mary.
An oblivious and negligent boy... A dandy old man with energy and lust to spare... And a cheerful young girl, with a secret taste for danger and beefy older men...
What will happen between them? Of course, a whole bunch of flirtation, cucking and wild sex.