Sherlock sat in his normal chair near the fireplace. His fingertips pressed together, he held his hands up to his face, staring deep into the roaring fire. Nothing John did would make him stir. He had even accidentally dropped a mug on the kitchen floor, causing a huge clattering crash. But he never moved once.
"I wonder what he could be thinking about?" John mused as he swept the remains of the unfortunate mug with a broom.
…
"I will burn the heart out of you..."
Those words raced through Sherlock's mind over and over as he stared into the warm, blazing fire in their living room. But the embers were far from comforting, even on such a cold winter night.
"I will burn the heart out of you..." This is what the last cryptic message Sherlock had received had said, and he had kept it hidden from John. For reasons he couldn't say, the note had worried him. He had been informed by many people that he didn't have a heart, and Sherlock agreed with them. He himself did not have a heart, it belonged to someone else.
Sherlock jumped up as sparks from the fire flew toward his chair. John had just thrown a log into the fire, disturbing it and sending the embers up. Sherlock stared at John, wide-eyed, like he was Santa himself. Not that Sherlock knew who Santa was anyway.
"Sherlock?" John looked at him. "Sherlock, you alright?" Sherlock was now standing up, staring back into the fire.
"What? Oh yeah..." He coughed. "Just fine."
John looked skeptical.
"What's wrong? Did you get another one of those weird messages?"
"No," Sherlock lied. "No, nothing new..." his voice started to fade, and he looked even paler than normal. He stumbled forward and started to fall onto John's shoulder.
"Sherlock? Sherlock? Oh my god, what's wrong?" John put his arms on Sherlock's waist as he tried to support him. "Should I call Lestrade, or Molly, or an ambulance, or-" He realized that struggling to hold Sherlock up was useless and helped him down on the ground. Sherlock wrapped his arms around John in a tangle of limbs, and snuggled deeper into his shoulder and chest.
"Sherlock?" John was shocked at this sudden display of emotion from his sociopath flatmate. But he did nothing but weave his arms across Sherlock's back.
"John?..." Sherlock asked, his voice slightly muffled by John's sweater.
"I'm here, what is it?"
"Please..." Sherlock sniffled. "Be careful. Please."
"What? I don't understand..."
"Just promise me you'll be careful."
John still looked confused, but decided not to press Sherlock any farther.
"Of course. I promise."
Sherlock sighed quietly, and started crying softly into John's shoulder. He quickly sat up again with a sniff and wiped his checks on his shirt.
"Thank you. Thank you, John." He stood up and walked toward the kitchen, leaving John, looking dazed, on the floor. "Cup of tea?"
Sherlock spent the rest of the night pretending nothing had happened, though he was wondering where his favourite mug had gone.
But there was always something nagging him in the back of his mind, telling him, that this was far from over, that his heart would never be safe. And he would do anything to save John from burning.
"I will burn the heart out of you!"