Shadow Captain (Revenger, #2)

Two sisters ran away from home to join the crew of a spaceship. They took on pirates, faced down monsters and survived massacres . . . and now they're in charge. Captaining a fearsome ship of their own, adventures are theirs for the taking - and there's hoards to loot and treasures to find in the darkest reaches of space. But the rules are also more relaxed out on the fringes, as they're about to discover . . .