Part of the storyline theme deals with slave owner's missusing their slaves in a sexual manner. It is implied throughout the film.
When August King arrives with the slave girl at his cabin, she has him rub a balm on the scratches on her back. As he does he starts to caress her back, but stops short to resist temptations. There is nothing more throughout the film with physical contact between the two of them, except for a breif (non-sexual) hug when she leaves on the trail.
NOTE: As mentioned before, it is implied that the slave owner has slept with this slave and mistreated her. When the slave owner is drunk, he claims that he went to sleep and woke up with a pillow in his arms and she was gone. Throughout the film, sexual references are mildly implied. Parents concerned with sheltering their children until an older age may wait to show this film until 15 or 16.