They do, if reluctantly

"Lean over the back of the sofa, Frannie!" Sarah barks.

You are kind of surprised at the brunette's tone. So, apparently, is Frannie. She just looks at her classmate's scowling face and quietly does as she has been told. You watch, trying not to look like you are being entertained by all this, from the opposite end of the sofa Frannie has bent forward over. The bleached blonde's boobs are pressed against the sofa cushions, her lush ass jutting high in the air. Sarah takes her position just to the side of her.

SMACK!!

A powerful open-handed blow reddens the right cheek of Frannie's ass. Frannie arches up from the sofa.

"Sarah! Not so hard!" she pleads, facing her Chem Lab. partner.

"Shut up and stay bent over 'til I say so!" Sarah hisses, pushing the girl back down over the back of the sofa.

You try not to chuckle at the determination of the babysitter.

You are quite amazed as the little brunette begins to deliver blow after blow to the blonde's chubby ass. Sarah's hand at the small of Frannie's back keeps the wriggling and squealing blonde in place as she continues to rain blow after blow, alternating the cheek she hits with each swat.

"This is all your fault, Frannie! And I'll be damned if you're getting me swatted because you were screwing around!" Sarah near-shouts at the sobbing girl before her as she continues.

"Please, please, make Sarah, stop, sir! I'll do anything!" Frannie pleads to you through tear-filled eyes, her mascara running.