Derek covered his face with his hands when Aubrey and Laura started discussing her stamina. He knew the hand on his back was meant to be comforting, but she was practically pimping him out, so it felt more like forceful encouragement.
"Stop talking about stamina and sex," he said, muffled by his hands. "At least when I'm in earshot. My sister and I have a strict don't-ask-don't-tell policy. At least we did." He raised his head and shot her a glare before stepping away. "If you're going to have sex with my sister, don't tell me about it after, okay?"