Marika Katou is a normal highschool girl, living somewhere in space. At school, she enjoys being in the yacht club, and after school she works as a waitress at the Cafe "Lamp". One day, she is suddenly asked to become captain of the space pirate ship Bentenmaru.

Its Marika versus Quartz, Marika has rallied all the pirates to confront Quartz in a winner take all battle. But no one expect for three Grand Cross battleships to appear.