Rose R "Bad Revision"

You've just opened a letter from your step-daughter's university. She's failing at one of her subjects, and Rose is worried you're going to tell her mum. You've offered to help her revise, but Rose is on to you. She's fully aware you have a naughty crush on her and can spot the hard cock growing in your pants. She'll have some fun with you and agree to revise with you once a week, but only if you don't tell her mum!