I enjoyed this probably more than I should. In the future a plucky girl who's in that's school's space yacht club finds out she's an heir to an odd fate. When that planet fought for it's independence it gave out letters of Marque to space pirates in return for aid. Those letters are still legal and the heirs of those original captains can become "legal" space pirates. Will our plucky girl take up the family trade? Who is the stern girl that just joined the school? Why is it every teacher seems to be a space pirate? All this and more will be answered.
While it is a light hearted romp I enjoyed that it wasn't stupid. The creators gave their background some thought and it's a consistently interesting version of the future. I also liked that they took their time in interducing the premise. They didn't just slap her in a pirate ship on the first episode. Instead they let things build so we can get to know our character better. Sure we've seen her type before in anime, but she's likeable and more importantly smart. She might not be trained to be a pirate, but she thinks things out and makes good decisions (mostly).
So I liked it, and I think any anime fan will as well. Enjoy it, bodaciously.