Thousand worlds

Min, a thirteen-year-old girl with fox magic, stows away on a battle cruiser and impersonates a cadet in order to solve the mystery of what happened to her older brother in the Thousand World Space Forces who is accused of abandoning his battle cruiser to go in search of a mystical object called the Dragon Pearl. In her quest to find her brother and clear his name, Min will have to use her fox magic to fight off gamblers, pirates, and ghosts.

"When Min the fox spirit and her ghost brother Jun are sent on a goodwill mission to prevent war from breaking out, they end up getting stranded on a death planet behind enemy lines"--