There is a teleporter shrine in the basement you can use to leave, or you should be able to go to the ground floor, and just head out the way you came in.
The only sailor you need to rescue was the one on top of the pillar, which you have done already if you are inside the battle tower.
If you are past the fight with Laiken and done the first dragon battle, there is a teleporter shrine in the master's chambers, down the elevator behind the throne.
