Princess Serena keeps the slave trapped in the smother box so he wont run away from her and he wont be able to fight back while she torments him. His face is all exposed and invites his mistress to sit on it. Princess Serena takes a seat with her thong ass! She now sits firmly on his mouth and his nose is stuck between her hot ass cheeks so he has no chance to breathe. Thats exactly what Princess Serena wants, depriving him of oxygen and brutally tormenting him, and for this every method is fine by her!