Before her mother died, Shelby promised three things: listen to her father, love as much as possible, and live without restraint.

Those Promises become hard to keep when Shelby's dad joins the committee for the Princess Ball, where girls must take a vow of purity - no "bad behaviour", no breaking the rules, and definitely no sex. Torn between Promises, Shelby makes a decision - to exploit a loophole and lose her virginity before taking the vow.

But somewhere between failed hookup attempts and helping her dad plan the ball, Shelby begins to understand what her mother really meant, what her father really needs, and who really has the right to her purity.