A high school boy marries his alien teacher to keep her secret, then has to actually live with that choice. The show treats this absurd premise like a real relationship: the comedy comes from two people learning each other, not from the setup itself. By episode twelve, you understand why they needed each other more than why the premise ever made sense.

Kei Kusanagi is a high school student living with his aunt and uncle. One day he spots a strange glowing woman by a lake and learns she is Mizuho Kazami, an alien officer of the Galaxy Federation. She also turns out to be the new teacher at his school. As the two gradually get to know each other, a romance develops between them. When the school principal discovers their relationship, the answer is marriage. Now the newlyweds have to hide their union from Kei's high school friends and from the Galaxy Federation too, while one romantic complication after another keeps cropping up. Blending comedy, drama and science fiction, the result is a fragile, funny love story between an alien and her student.