John had only been in the flat for five minutes when he smelled the ammonia. "Sherlock?" he called, trying to find the source of the odor. He wasn't in the kitchen, or in the living room. The bathroom. He knocked gently on the door. "Sherlock? What are you doing?"
"Nothing, John. Go away."
John pounded somewhat more insistently. "Sherlock. I know you're not cleaning in there and you know that there is to be no science in the bathroom."
There was no answer.
"I'm coming in. I hope you're wearing trousers this time." He swung the door open to see Sherlock leaned over the sink, looking shocked. He was shirtless, a towel was draped across his thin shoulders, wielding a bottle. A bottle of dark hair dye.
"And here I was thinking you'd gone and melted the bathtub or something equally destructive."
"I didn't think you'd actually come in."
"So are you really a natural blonde then?"
"Auburn." He replied with distaste.
"Not a fan of gingers?"
"It's auburn. I just don't like it. Sherlock means 'fair haired' in old english. My name wasn't some great irony to my parents. I really am fair haired."
"I never made that connection."
"Of course you didn't." He said, matter-of-fact.
"Right. I'll just...go...then."
"Please do." John started to back out of the room. "Oh, and John. Please don't tell anyone."
"Wouldn't dream of it."