From the day his parents named him, Nasa Yuzaki has felt connected to outer space...whether he likes it or not. His efforts to outperform the space program veer off course when an accident introduces him to Tsukasa, a mysterious girl with strange powers. Is she an alien, a moon goddess, or something else? Since she insists on marrying him, Nasa will have plenty of chances to find out!

Tsukasa and Nasa are closer than ever to unlocking the mystery of her eternal curse, but Tsukasa finds herself haunted by memories of the past. Things only get more emo when the newlyweds are called upon to tend the Yuzaki family grave, which reminds Nasa of his eccentric grandfather, a WWII vet who claimed to have met a demon. On the bright side, Nasa finally gets the technological inspiration he needs--by obsessing over swimsuits!