I will ruin you.
I make this slave jerk himself off in front of me with thick gobs of my spit, taunting and teasing him with my filthy feet and smelly, sweaty armpits... humiliating himself by getting so turned on by such foul things.
After he shoots his shameful load, he's instructed to the floor to lick up his cum and lament the fact that only the most depraved of acts will get him off.