"No, we certainly can't. They'd ruin all the fun." Sara said in an amused voice as her eyes followed the older Slytherin's tongue as it traced her lips. "A wager?" she asked, raising a brow as she was broken from her gaze. She rarely turned down a bet. "What kind of wager? And what stakes?"
Sara could now clearly see the effect her fingers were having on Clara and se trailed them up more, teasing the edge of her knickers at the edge of her arse. "If me just teasing you like this-" She emphasized by digging her nails in lightly to the firm flesh near the bottom of Clara's arse, "-makes you squirm, then I have no doubt in my mind I can make you scream."
Grinning, Sara sat up fully, hand still on Clara's thigh, and leaned so her mouth was right under Clara's ear, breathing hot air on too the sensitive area of skin and so her ear was near Clara's mouth. "Do tell..." she breathed, her fingers drawing circles on the back of the girl's thigh.