After Voldemort's defeat, Lupin visits Charlie at the dragon-sanctuary, only to find a familiar Potions Master, thought dead, working there. Snape has been greatly changed/damaged/disabled by Nagini's venom. (Prefer Snape/Lupin or Snape/Lupin/Charlie) He may or may not have been infected with snake-lycanthropy because of Nagini's venom - Snape is now a were-snake! (optional)