Her hand

She gives your ass a stroke, running her nails along your soft flesh. Seeing the fear in your eyes she remarks "What's the matter, scared of a little spanking? Or are you afraid that you're going to enjoy it?"
To your shame, your previously limp cock has begun to stiffen against her lap. She pulls your shirt up with her left hand and then presses down on your back, holding you in place.

Slowly she raises her right arm, making you wait for it. Then quickly, she brings her arm down, her outstretched hand whips into your right cheek. SMACK You recoil and instinctively try to move away, but her left hand prevents you from squirming much. Miss Locke lets out a malicious laugh and raises her hand again. SMACK Harder this time. Again SMACK You try to stifle a yelp of pain, probably best if she doesn't know how much it hurts. "What was that? Did you want to say something?" SMACK "It sounded.." SMACK "Like you.." SMACK "Were trying.." SMACK "To tell me something". You hold your nerve and remain silent. SMACK SMACK SMACK SMACK SMACK

She continues, alternating from left cheek to right. You helplessly kick your legs and writhe on her lap, trying to ignore the pain. "Be still!" she commands and tightly pinches your now red ass, resulting in a fierce sharp pain. You do as you're told and stay still as she gets back to the spanking. SMACK SMACK SMACK Each hit hurts worse than the last, and you desperately want it to stop. Every spank causes you to lightly push against her lap, your erect cock grinding against her thigh. She giggles to herself and poses the rhetorical question "You're loving this aren't you?" Maybe you should have swallowed your pride and worshipped her feet. SMACK SMACK SMACK You wince, preparing yourself for another spank, but there's a pause. "Ok, that's five minutes, now you've had a taster, I'll let you pick what implement you'd prefer for the remainder of your punishment. The ruler? The paddle? Or are you enjoying my hand too much?" she asks, lightly slapping your ass.