Harry had been out in the woods under his cloak waiting and watching. Voldemort was only feet away from him and he knew that the battle could be here and now but he knew he was not yet ready. They needed to destroy the last of the horcruxes first. He was surprised though as he watched for he had come to destroy Nagini in hopes that they would have only one left and the battle and the war would end soon. He was not surprised that the snake was there with Voldemort, but he was surprised by who had come into the clearing.
Severus had been in hiding since he had stopped Draco from killing Dumbledore on the tower that night, having been found out as a spy. Dumbledore had sent him away from the school for his safety and that of the school and no one had seen him since. Harry had flashes of working with him in occulemency training and he had seen the man risk his life. Severus had not only protected Dumbledore up on that tower but he had saved Harry as well.
He knew Severus was a dead man for showing up there, a price put on his head. The only Death Eater who would not have killed him was Lucius. Both men had been spies since they were in school. But Voldemort would be out for blood.
Severus bowed his head to the man. "I have come My Lord to offer my services to you again. I have found a way for you to enter the castle as soon as tonight."
Voldemort sneered at him. "The last of the wards are down and I do not need you help. There is no saving your scrawny neck now."
Harry almost shouted out to warn Severus but he was reminded that it would mean his death and those in the school. He watched in horror as the huge snake sunk his fangs into Severus in the leg. He knew that the fangs of the snake were venomous and that Severus would be dead in no time at all. But he watched in shock, when Severus pulled out a hidden dagger and sunk it into the snake. The snake fell dead along the grass, there having been basilisk blood on the knife.
Voldemort raised a wand but he stopped. "No matter, it is still no victory for your side. You will die the long painful death you deserve you traitor scum."
Severus was sinking to his knees. "They will destroy you; you will come to an end once and for all. Your hours are numbered Tom."
Though Harry had expected him to be hit with a killing curse for calling Voldemort Tom, the dark lord simply drifted away with his other men. He knew that Severus was just trying to egg him on into killing him. Nagini had not put enough poison into him and usually the snake would have either sunk more in or eaten him. It would take at least an hour for him to die but even if he was not the only potions master who could have brewed an antidote there was no where enough time. Severus was a dead man and Voldemort knew it and wanted the man to die a long painful death.
When he was sure they were gone Harry slipped out of his cloak next to Severus. He was not sure why he cared but he could not allow the man to die alone here in the woods. Because of his sacrifice Harry had still had Dumbledore by his side to help him hunt horcruxes and even finish his last year. He took his NEWTS two days before, odd to think they took them on the verge of battle but they had. He knew Severus had sacrificed so much for the war and he would not let him die alone.
Severus looked at him in surprise. "Harry get out of here, there is the one horcrux let to be destroyed. You need to get to safety."
Harry shook his head. "It will be dawn before he attacks and Dumbledore and the others are looking for the diadem. I will not allow you to die alone."
Severus leaned against him though he hated to do so. He was reminded Harry was the son of his best friend, of his sister, Lily. Only his friendship with Lucius had compared to that but he had never been able to look past the appearance of Harry for he was the image of his dad. But some how he found such comfort in those green eyes and though he knew he was dying he found such peace in the arms of Harry. He was grateful beyond words that he was not dying alone.
But a figure appeared from the woods and they were certain they were dead before the hood was pushed back and Severus realized that it was an elf, something not seen in the UK in centuries, other then in their hybrid form, veelas. Veelas were a mix of human and elf but only the veela traits carried on.
The elf looked at Harry. "There is a way for you to save this man, I see you have the purity of magic to do it. If you are willing."
Harry looked at Severus and back at the elf. "I am willing to do what is needed. He saved my life; I will do what I must to save his."
Severus tried to stop Harry for he knew what the spell entailed but he could not seem to find the words. He knew that it would require a binding of their powers, so that if Harry survived the final battle so would he. He also knew that if the spell was not completed in one years time they would forever be linked meaning if Severus got hit by a muggle car and died, Harry would drop dead. Harry had no idea what he was getting into but for some reason Severus could not find the words to stop him, could not find the words to make Harry not take the pledge. As their blood was mixed by the elf he knew Harry had made the ultimate sacrifice for him.
The elf pointed towards the school. "You must go and fulfill your destiny. I will bring him to safety. The battle awaits young Harry."