Probably done before but I'm too lazy to look it up.
Cute-as-a-button Sally enjoys sex with her BFF Milly and with her toys, but all her friends seem to be losing their virginities and she doesn't want to be the last. However she doesn't fancy any of the boys at school.
Milly says she knows the ideal person but Sally can never know his identity, so has to agree to be blindfolded, restrained and wear noise-cancelling headphones.
Sally reluctantly agrees, and lets Milly tie her up etc.
Enter Sally's dad, who gives her a wonderful time.
Afterwards Sally begs to know her lover's identity because she wants a repeat, but Milly refuses to tell. And Sally's dad keeps silent too rather than risk his marriage.
AJ