"I'm sorry, Theo," he said firmly as he fastened the diaper around her waist. "Your body belongs to me, and right now I decide when you get to feel good. Once your time-out is over and you've proven that you can behave, maybe we can talk about letting you cum." He placed a hand on her hip before lifting her up off the bed and carrying her back into the living room where she would sit in time-out for the remainder of the day.

"Theo," he said, his voice stern but gentle. "I know you want to feel good, and I promise we'll get there eventually. But right now it's important that you understand who's in charge and what your place is." He ran a finger down her cheek, brushing a strand of hair behind her ear. "Just sit here quietly and think about how you can be a good little sister from now on."

Her body ached for release, but she knew better than to push him.