Holmes sighs and settles his hand on Watson's back, his thumb stroking slowly back and forth over his spine. It's inevitable that he talk about this, but he's actually glad for the opportunity; he's been carrying around the weight of his journey for a while now, and he's grateful to be able to share some of that burden with Watson now.

"It wasn't really a question of choosing Tibet. It just happened to be where I was when Moran left me to die in an opium den." He sighs again and closes his eyes, trying not to recall any of his thankfully fuzzy memories about that time. He strokes his fingers up Watson's back to stroke through his hair.