Dawson Ida, a young man who has just graduated second in his class from the Amato Imperial Academy, is appointed as a 'Special Lieutenant' due to the scheming of the academy's principal. His role is to command a privateer spaceship and operate as a space pirate under the control of the Amato Empire, targeting the Human United Nations Space Union (SUN). The only support he receives from the Amato Empire is the privateer ship 'Mandible' and initial supplies. His only companion is an AI for communication, Oine. Despite the unreasonable nature of his mission, Dawson uses his false identity as a pirate to interact with other pirates and take actions that harm the SUN and benefit the Amato Empire. No one knows what kind of military career Dawson will have at the end of this pirate mission.