The narrative revolves around a lively high school student named Marika. She stays occupied with her involvement in the space yacht club and her part-time job at an upscale retro café. Suddenly, two unfamiliar individuals emerge and assert that they are subordinates of Marika's deceased father. These strangers demand that she take charge of the Bentenmaru, a compact ship inherited according to a privateer agreement made during a war of independence a century ago. As per this pact, the command must be passed down to the direct descendant of the captains. Thus, Marika is thrust into a new existence as a space pirate.
Mouretsu Pirates won the 44th Seiun Award for Best Media in 2013. The series was released on Blu-ray and DVD by Sentai Filmworks from January 8, 2013 to March 5, 2013. The company later republished the anime as a complete collection in the same formats on October 7, 2014.