Is there a soft/hard drug which looks very similar to pepper? 

Does it look like pepper as in powder, or more like strands of tobacco as you have written later on?

Also is the only method of taking it snorting or are there other ways, and have you tasted it if so is it bitter like perhaps a paracetamol or other tablet might taste?

At a wild guess here if it's brown strands it could be mushrooms, but it's likely they would have the caps ontop of the stems, also there not meant to be snorted.

If it's more like a fine powder light brown, maybe even greyish and tastes bitter it's possible it may be heroin.  It's hard to say without seeing it, and even then it could be anything, What makes you think it could be a drug?  It could be snuff lol Thats light to dark brown like pepper and meant to be snorted.  Some people snort it instead of smoking tobacco I think it taste vile, perhaps even a little spicy.  Sorry I cant be more specific as I said could be anything

Thank you for your rapid response. The powder in question was left behind after a suspected drug user left a restroom. The amount he left behind was minimal. Either there was so little to not have a distinct scent or it was in itself scentless. It wasn't tobacco. The substance was like shavings and peppery. It was predominantly brown/dark brown. It was found in a bathroom. It couldn't have been smoked. It wasn't injected and it wasn't a part of a pill.