Sherlock had had a fascination with John’s scar from the first. Unable to stop himself for touching, frowning as John jerked away, trying to hide it.
“Sherlock!” John gasped in shock, not having heard him come in, though not as surprised as he should have been that Sherlock didn’t have any sort of decorum about entering his room as he dressed. “What are you doing?”
Sherlock reached out hesitantly toward his back, and John twisted to see the edge of the ugly scar tissue there. “May I?” Sherlock asked.
There was something about his tone that had John nodding before he really considered it. Sherlock’s touch was firm and sure, and John gasped at the contact, the nerves unsure what they were feeling.
Sherlock paused, and gave him a look, silently asking if he’d hurt him.
“It’s fine. Just strange.” And it was. John felt it, but it wasn’t like a normal touch. He barely felt where Sherlock’s hand rested, but John could feel it further down, almost like Sherlock’s hand was lying on his side rather than his shoulder. It was very strange.
Sherlock’s fingers curled, head cocking to the side as John drew in a sharp breath, but continued his exploration, tracing the edges of the scar, ghosting over the ridges and the smooth skin. When he leaned forward and ran his tongue over the area, John gasped and twisted away fully.
The next time was after things had changed because of the first time. Sherlock couldn’t keep his hands to himself, and of course, John misunderstood. Sherlock set him straight. It wasn’t about sex. Not at all. Everything but, apparently. It was odd, but this was Sherlock and it staved off any panic that John might have had about the relationship that they had.
John had awoken to the feel of his shirt being pushing up, and he’d murmured a protest as it was tugged over his head. It didn’t even process at first what Sherlock was doing, John just knew that it felt good, Sherlock’s fingers and mouth on him.
After that it really wasn’t so strange, just another of Sherlock’s quirks, and John had to admit that it wasn’t so bad.
Then came the day Sherlock pulled a knife on him.
“What the blood hell are you doing with that?” John said as he scrambled out of his chair.
“Now, John,” Sherlock began.
“Don’t ‘now, John’ me, Sherlock. Explain what you think you’re doing,” John said as he backed towards the door. He wasn’t scared, never of Sherlock, but sometimes he just took things too far.
Sherlock had the grace to look flustered and set the knife down, walking forward, hands up in placation. “I want to mark you. A good memory. A reminder.”
John sighed, dragging his hands down his face. Of course, Sherlock had come to the most complicated conclusion. “And you couldn’t have just suggested a tattoo or something?”
Tilting his head, Sherlock inched forward. “But you would have said no.”
Well, that was true. “And you didn’t think I’d say no to this?”
“It’s not the same, not at all.”
“Explain it to me then.” By that time, Sherlock was at his side and John tugged him towards the couch. Of course, Sherlock all but draped himself over John despite the fact that the majority of it was empty.
“Scars are natural. Everyone has them. Normally they are a reminder of bad events in a person’s life.” Sherlock paused there, letting the implication sink in.
Realization dawned, and John’s heart ached a little. “Sherlock, nothing could make me forget you,” John said as he trailed his fingers through Sherlock’s curls.
“Is that a no?” Sherlock asked.
John rolled his eyes. “You know it isn’t, but not today,” John said, shoving Sherlock off him.
When the day finally came, John wasn’t as nervous as he should have been as he reclined on the bed in nothing but his pants, the plastic underneath the towels he was sitting on crinkling every time he moved. “You’ve practiced?” John didn’t ask where because he really didn’t want to know.
Sherlock shot him a look.
“And those are sterile?” John asked, motioning towards the scalpels.
“Yes, John.” Sherlock settled between John’s splayed knees, pulling one of John’s thighs across his lap.
John shivered as Sherlock’s fingers ghosted over his inner thigh. Of course, Sherlock would pick a place like this, someplace hidden, ‘for his eyes only’. “Get on with it.”
And Sherlock did. The first bite of steel into flesh was almost painless, but when the pain finally hit, it left him gasping, and Sherlock paused.
John shook his head, it wasn’t that bad, mostly unexpected. “Keep going.”
After a while, the sensation went from painful to, while still painful, also strange. Endorphins, John knew. He let himself drift in the sensation.
The tug of skin that hadn’t quite been cut through all the way brought tears to his eyes, and his gasp brought a murmured apology for Sherlock.
John sank back down into the sensations again. It was almost sensual.
And finally it was over. The cool spray of antiseptic over the wound brought shivers to John, and for the first time, he looked down at it, deep red against the white of his thigh.