When Snape didn't emit any objection, she lowered herself to her knees, and ran her tongue across the tip of him. He groaned, very loudly, his hands flexing at his sides. Her eyes flitted between his erection and his face, seeking to take stock of his reaction, while she tongued the leaking slit of his cockhead. His nostrils flared, his eyes getting impossibly darker, a small spasm tugging at his left cheek.