Sirius Black and Hermione Granger's Practicality

A new Muggleborn Protection Act decrees that all muggleborns 17 must marry a pureblood within a month of turning of age. Due to a rush to find a partner, her use of a Time Turner messing with her actual age, and getting late to the game, Hermione is left with one less than ideal option for a husband, with no chance of divorce ever: Sirius Black. AU; set in 5th year; SB is free.