Blood Knight SSHG

As he lay dying after being attacked by Voldemort's familiar Nagini, Severus Snape is presented with a choice. He can either die as an unsung hero of the wizarding war against Voldemort or he can chose to live again as the son of an ancient Vampirian king. All of it gets complicated when he finds himself locked in an ancient war and Hermione Granger is dragged into it all.