Vanessa walks into her step-son's room with a chart.
It outlines how her reward system works.
For every C her step-son receives, he can select a body area which she's unclothe and let her step-son fondle for the day.
Three Cs make one B.
For every B her step-son receives, she gives him a handjob, unclothed or clothed (step-son's choice)
Two Bs make one A.
For every A her step-son receives, she gives him a blowjob, unclothed or clothed (step-son's choice)
For anytime her step-son gets consecutive As, step-mom will have sex with him.
Vanessa's step-son ...

Vanessa walks into her step-son's room with a chart.
It outlines how her reward system works.
For every C her step-son receives, he can select a body area which she's unclothe and let her step-son fondle for the day.
Three Cs make one B.
For every B her step-son receives, she gives him a handjob, unclothed or clothed (step-son's choice)
Two Bs make one A.
For every A her step-son receives, she gives him a blowjob, unclothed or clothed (step-son's choice)
For anytime her step-son gets consecutive As, step-mom will have sex with him.
Vanessa's step-son smiles and hands her two tests, one marked as C and one marked as B.
Step-Son hungrily starts groping step-mom, as step-mom starts to handle his cock.
Step-Mom starts sucking on his cock, telling him how great his cock is, and asking him if he likes having his step-mom sucking on his cock.
After a good amount of sucking, step-son asks step-mom to turn around so he can fondle her ass.
She obliges and turns around to let him fondle her ass.
He hugs her, fondling her tits and grinding his cock on her ass.
He can't help himself, so he sticks it in her, and step-mom yelps in surprise.
He tells step-mom he couldn't stop, and he had to stick his cock inside her, and promises to bring her consecutive As.
Step-Mom tries to object and say that's not their deal, but her step-son holds her close and keeps pumping.
Step-Mom is too turned on to object anymore, and agrees to his promise of bring her As later.
They fuck in various positions until the step-son cums on her face.
She sucks his cock clean and reminds him to bring her those marks.