Over the course of Sherlock's life only one thing has ever been a constant. It isn't his annoying older brother, parents, friends, security, shelter, money, food, or even water as it is for most people. It's his skull, who was lovingly dubbed Yorick by a 6 year-old Sherlock.
The skull could always be seen sitting on the ancient and proud maple desk on the far side of his father's large study. Day after day Sherlock would pass by the ever locked and forbidden room, and out of the corner of his eye he would see the skull- damned to sit for eternity smiling at everything with unseeing, but seemingly wise eyes. At least it seemed so to Sherlock, who after the sudden death of his father only asked for the faded white skull in the study. He would often sit and talk to Yorick for hours upon hours after school each day.
He talked about the sheer stupidity of his classmates (honestly, who doesn't know binary?), the cruel and scathing taunts of the stupid classmates, his current experiments, chemistry, and anything else that popped into his head. When questioned why by Mycroft, his only response was, "He doesn't laugh at me when I talk like everybody else." Mycroft chuckled at the oddness of talking to an inanimate object as he walked away.
Wherever Sherlock went, Yorick went. He would hold long conversations with the old skull as it sagely listened to the ramblings of the young, too-thin genius.
Yorick was temporarily forgotten about while Sherlock was at Uni. Oh, he was still there, sitting on the flimsy, scratched up, and vandalized desk in the corner of Sherlock's dorm room. Hour after hour he would sit there as Sherlock was running about campus performing experiments in the chemistry lab and throwing insults and deductions at all who dare approach. And he would sit there hour after hour as Sherlock perfected his 7 percent solution, shot up, and started withdraws.
After Uni and several rounds of therapy Yorick was back as the main thing in Sherlock's life, even listening as Sherlock thought through his cases with him. The skull had panicked Lestrade for a moment when he first saw it, but like everyone else they soon came to accept the old skull as just another part of the socially awkward and lonely genius.
Then came John. Yorick watched as Sherlock started leaving him behind more and more and talking to him less and less. Sherlock still had long conversations with Yorick when John was unavailable, even if Yorick now never left 221B with the lanky detective.
"Mrs. Hudson took my skull," Sherlock complained to John one day. "Is that a problem?" questioned John. "No. No, for once I don't think it is." Sherlock has a new skull to talk to and this one can talk back. And Yorick… well he's now raising some new detectives in a biology classroom.
My first fic! Please be kind!