Sherlock closed his eyes and shook his head. "Another time, perhaps." He said, with a bit of finality in his voice. "Not now. I.. can't."

He turned his head to the side, away from John.

Sherlock ran his hands through his hair, biting his lip hard enough to draw blood. He couldn't fall into one of his dark moods. Not when things might actually be starting to look up.

Not now.