On a 7-9, you do so, but it will cost you.

"I need a ride then to the prom," Lily's voice was nervous and unsteady as her brother stood uncomfortably close to her. Had she more presence of mind, Lily might have tried to leave the room, but she was more preoccupied with the worry that things might not go as planned with Mark tonight. A hand on her cheek brought her back into the present; her brother's rough and calloused hand contrasting with her soft delicate flesh.

"Sure," he replied evenly as he walked over to the door to make sure it was closed completely. "But, I'm kind of busy, so it might be awhile."

Lily's eyes widened; she wouldn't have long to try and catch up with Mark and apologize for being so late, "But I need to get to the Prom quickly. What if Mark finds someone else?"

A grin crossed over her brother's face as he clicked the lock on the door sealing Lily's fate, "I think you could do something for me then... why don't you do what you just did for uncle earlier?"

The words shook Lily to the core as realization slowly dawned: Her brother must have seen the despicable things she'd done earlier. A red tinge colored her cheeks, but she knew there was little she could do about the situation. She needed a ride and besides it couldn't be any worse sucking off her brother right? It was only oral sex...