The Second Wizarding War is over - so what happens now? As her comrades packed up and moved on with their lives, Callie Warbeck stayed behind. And her former head of house, with whom she shares a complicated past, is forced to coexist with the girl he'd wanted nothing more to do with. Sequel to my first story, The Only Slytherin.
The story of a girl you never got to meet, but who was there every step of the way.
After leaving the Death Eaters and joining the Order, Snape writes to Lily to explain everything, from calling her a mudblood in fifth year, to joining the Death Eaters, to giving Voldemort Trelawney's prophecy. This is literally that letter, written in 1980/81, before Lily and James are killed.