use vibrator

"Hey, sis, what's that?" Yuki asked, her voice trembling slightly.

"Oh, this?" Rei said, holding up a small, discreet vibrator. "It's just a little something to make sure you stay nice and quiet while we're here."

Yuki's heart sank. She knew what that meant. Her sister was going to use the vibrator on her, in public, and there was nothing she could do about it. Rei had always been dominant, but this was taking it too far.

As Rei pressed the vibrator into Yuki's pussy, she felt a wave of shame wash over her. She had never been so humiliated in her life. But before she could even process what was happening, Rei let go of the vibrator and led her to a new location.