"How much?" the brother asks, his eyes locked onto his sister's curves, the outline of her nipples visible through her thin shirt. "A thousand," she replies, her voice steady despite the butterflies in her stomach. He counts out the bills, his hands trembling slightly. She takes the money, tucks it away, then slowly begins to undress, her eyes never leaving his. "I've never done this before," he confesses, his cock straining against his jeans. She smiles, a wicked glint in her eye. "Today, you'll do it all," she promises, dropping to her knees, ready to teach her baby brother the art of pleasure and profit.