So here are you daily dose of feels today! Yeah I wrote this as a friendship piece, because I don't ship Johnlock, but if you want it to be… well I won't stop you. Just so you know Sherlock is Snape…
Sherlock should have known he wouldn't make it out alive. Spying for the Dark Lord, easy. Spying for Dumbledore, slightly harder, but still not above Sherlock considerable talents. But Sherlock hadn't been prepared to die. Admittedly he had no idea what he would have done after the war, not with everyone thinking he was a soulless murderer and it wasn't Sherlock.
A noise from the side. Sherlock turned his head to look. It was him. His face was a mixture of horror and disgust, at Sherlock, who was trying, with shaking hands to staunch the flow of blood from his neck. Sherlock knew he would have to time to tell the boy the truth.
"Take…it" he rasped, as he poured his thoughts and memories out to the boy. The boy's hands were shaking as he gathered the memories in a bottle that the Mudblood had conjured. Sherlock could see the memories in his mind's eye as he let them go…
17 years ago
Sherlock appeared on to the street. He had to find out, had to see for it himself that it was true, otherwise he refused to believe it. The Watson's cottage was clearly visible and Sherlock refused to acknowledge what that meant. He opened the door carefully, terrified of what he might see. The door fell to the floor with a crash. It had been blown apart. Slowly he ascended the stairs. There, half way up, was the cold dead body of Mary Watson. The bully who had always hated Sherlock, yet revered by everyone else. The person who made Sherlock's life practically unliveable. The person who had stolen Sherlock's only friend, the only person he had ever-no. He couldn't even say they word in his mind. He carried on upwards. Now he could a baby crying. The Dark Lord had failed to kill the boy, maybe he would have spared-
The door in front of him had been blasted apart and he stepped inside it. What he saw made him collapse against the door frame. The baby was crying in the cot, and on the floor…
John Watson lay on the carpet, still wearing his old grey jumper. His arms were twisted from where he fell. His unique blue eyes were wide open seeing nothing, staring at the son who he would never know. John Watson was dead.
"No" Sherlock croaked, trying to deny the evidence of his own eyes, "Please, God no"
He fell to his knees and reached out his arms
"John, please… wake up"
He took John in his arms and rocked his lifeless body. He let his emotions out and screamed in rage a grief. His eyes must be wrong, because John Watson could not be dead, there was no way.
I'm sorry John, I'm so sorry, I did this, I betrayed you, I'm sorry I'm so so sorry. I didn't want this to happen.
How long he sat there rocking John's body and sobbing he had no idea, but Hagrids bike awoke him from his grief. He gently placed John back on the floor, gave a whispered apology and apparated away.
Present
The boy put the stopper on his bottle of memories. He was the spitting image of Mary, only male. But his eyes were not Mary's. They were John's. Sherlock reached up and grabbed him by the robes.
"Look… at… me" he rasped
John's eyes met his own, and suddenly John's voice filled Sherlock's ears.
You're not going to take all day are you?
John, I'm coming Sherlock thought
Come on, you idiot! I've been waiting for ages!
Sherlock focused on the last living remainder of John Watson.
"You have…your father's…eyes…"
John's eyes met Sherlock's. But then something in Sherlock's seemed to vanish. Sherlock slipped away gratefully, hoping that where ever he was going, John Watson would be there too.