It All Comes Back To Snape

An A.U. where Hermione goes back in time to try and prevent the disastrous events of the Battle of Hogwarts. But she goes further than planned and ends up in a time before she was even born. Unable to go back forward, she's resigned to her fate and with the help of an enamoured teenage Snape, comes up with a plan to end it all before the events of the future can even occur. Lemons.