Tsukasa and Nasa are closer than ever to unlocking the mystery of her eternal curse, but Tsukasa is in a melancholy mood, haunted by memories of her past. The situation only gets more emotional when the newlyweds are called upon to tend the Yuzaki family grave, stirring up Nasa’s memories of his eccentric grandfather, a WWII vet who supposedly once encountered a demon. On the bright side, Nasa finally gets the technological inspiration he needs-by obsessing over swimsuits!