Kouji Aiba is a sixteen-year-old boy who packed his bags and left his home on Earth for the Liebe Delta and the training to obtain his Level 2 piloting license. He journeys to the space station accompanied by his childhood friend, Aoi Housen, whom Kouji discovers to his chagrin has enrolled in the Liebe Delta's flight attendant program. En route to the spaceport Aoi gives Kouji the additional unwelcome news that his younger brother, Yuki, is also to attend the Liebe Delta and in fact the brothers will be in the same flight class together. The list of Aoi's unfortunate news to Kouji is topped by her quipping that the boys' mother Mrs. Aiba had asked Aoi to look after the brothers while at school. Kouji's unhappy moodiness does not improve.