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The manga centers on a 10-year-old girl named Shirushi Nishizumi who lives in the city, and the alien she meets after it crash lands in Inzai. The alien needs "Aru Aru Energy" to be able to power back up its spaceship.
In a future where space travel has been made possible, Cetacea Aviation has begun to employ "space attendants" who are skilled in hand-to-hand fighting due combat hijackers who use their own bodies as weapons. Aoi Musashino is one such space attendant, but is unskilled and even calls herself a "clumsy, awkward, but cute turtle." Another space attendant named Yasaki, who has recently been transferred from local to interstellar flights, gets to know a boy named Laika, who says that his songs bring people misfortune.