the queen of the Sapphire Galaxy is ill, and you are the CHOSEN ONE to avenge her death. (well she will die soon so why not start early) crush your evil stepsister, the princess of Rhinoceros Galaxy, and the heir to the throne before all is lost. she is also your father. shhhhhh! but thats a spoiler so why did you read that!!? bullets should be dodged, not collected, silly.
It's a metaphor for eternal punishment.