Value disparity

"It should be straightfoward to discover what the universe considers the most degrading anal related punishment imaginable." Sora says.

Shiro understands immediately. "Okay, Sora, I challenge you to a game where if I win, you become my property. My ****. But if you win, I will give you one more gold piece."

Sora smirks. "Okay. Let's play 'buttcheek battle' again with those stakes."

A parchment appears in Shiro's hand. She starts to read it, and goes pale.

"What? What does it say?!" Sora asks, concerned.