Sherlock was not amused.
Far away from it.
John was talking about Mary again. He was always talking about Mary fucking Morstan. He hated how John talked about her. It made his blood boil, it made him want to grab a knife and stab it violently at Mary until she was nothing but a mess in the floor.
How dare John smile because of her, how dare he think and speak about anything other than Sherlock. That has to change. It will change. Someday, John will love Sherlock as much as he loves him, whether he wants to or not.
Sherlock will make John realize that he belongs to him and him alone. He will make him realize that they were made for each other, that they were perfect together and that nothing can keep them apart. Sherlock will claim John. He will make it clear to everyone that his John was off limits. He will make sure that he would be the center of John's world. He will consume him.
"-I think I'm gonna propose to her!"
"That's great."
oOo
Sherlock's plan was going great until John caught him.
He was just adding finishing touches to Mary's lifeless body and the door opened.
He saw it almost instantly. The way John's face was a mix of confusion, pain, and heartache. He can't wait to devour that face.
He abandoned Mary's body and walked towards John. He was a predator and he was about to stake claim to his prey.
His face was centimeters away from John's. He slowly placed both his bloody hands up to caress John's face, the blood darker in his pale skin. John was frozen and all he could do was stare at Sherlock's bloody figure as Sherlock moved one of his hands to the nape of John's neck and the other at his back.
"Mary's gone now John. You don't have to be afraid anymore because no one can finally set us apart. You're finally mine."
John was frozen and scared but managed to let out a shaky response, "What d-did you do to M-mary."
Sherlock violently pulled John closer to his body and was now holding him very tightly and painfully.
He dropped his head closer to John's ear and whispered with clear rage, "Nothing else matters anymore. You are only allowed to think and speak about me. I will devour you, John Watson."
He pulled John into a violent kiss, enough to draw blood, but he didn't stop. He drank every bit of John's blood and furiously used his teeth and tongue to explore John's mouth.
All John did was whimper.
Sherlock was fully erect now. He was grinding possessively at John's hips. His right hand travelled lower and started palming John's cock through his jeans and was surprised that it was already half-hard.
"Oh John", Sherlock moaned, "Are you hard just for me?"
Sherlock palmed and grinded faster. His lips travelled to John's neck and started kissing it passionately. He left marks and started biting at the skin.
Both Sherlock and John were almost fully covered with Mary's blood now. But it hardly seemed to matter. Sherlock was possessed with lust and desire while John was a mix of anger and pleasure.
"Mine. Mine. Mine. My John. My perfect, beautiful John."
Sherlock's dreams were coming to life.
John's nightmares were just beginning.
