Licking girls feet - FOX - All the dirt from my feet will be in your mouth

The narrative describes a character named Fox who enjoys walking barefoot and takes pleasure in having others clean her feet. She decides to test a new slave named Christina, who is tasked with cleaning the dirt from Fox's soles using her tongue. As Christina performs the task, the dirt causes her tongue to turn black, and Fox finds amusement in the situation, appreciating Christina's willingness to endure humiliation to please her.