Moribito (2016)

Balsa (Haruka Ayase) is a 30-year-old female bodyguard-for-hire. Her life changes when she saves Imperial Prince Chagum who is being carried away by a raging river. They then attempt to return the great egg of the water spirit, which is in Prince Chagum's possession to its source in the sea. Along the way, they are hunted by hired assassins.