It's been a some month since the war and Voldemort was defeated, snape is a hero for the wizard-world, Snape is now a professor of dark arts and potions, he had helped rebuild Hogwarts, there, everyone seemed to start their lives again... But he can't, he shouldn't be alive...

Minerva is the new headmistress, Slughorn has resigned, and now you will take over as DADA. Severus Will be potion Master as always. Thanks to Harry he has been recognized as a hero. He has a Merlin decoration whatever, he doesn't care... Severus sighs.

So there the first day he sees you enter the stuff room. Minerva is busy so you introduce yourself to everyone in the room, then it's Severus' turn to talk with.