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!

Romance is in the air among Nasa's students, but the course of girls' school love never did run smooth. Mishio confesses her feelings to Kaguya, who has trouble understanding human emotions--and consulting Nasa doesn't clear things up. Meanwhile, their mutual friend Jessie, struggling with conflicting feelings of her own, is determined to thwart the budding relationship by any means necessary. The sweet mystery of love isn't about to be solved anytime soon...