Mysterious brown: something brown on your skin or clothing that could be chocolate from a previously eaten snack or it could be dirt, or it could be shit. You can't be sure that it is chocolate or you could lick it off, so you have to clean it.
Oh no, I just ate a kit kat bar and then pet the dog and now I found something brown on my arm. That is some mysterious brown. I'd better wash it off with soap and water.
This is the secret department in the Ministry of Magic. It holds things such as prophecys. One of Harry Potter's battles is fought here.
Do you know where the secret Department of Mysteries is?
Blood that suddenly appears for no immediately obvious reason, such as accidentally scratching an itch and you hand comes back with blood on it.
"I just scratched the back of my head and now I've got mystery blood on my hand, can you check back there?"
The process when you're practicing a skill relentlessly but continuously fail to master it, but when trying again after a certain number of days, the skill comes naturally>
Zoe simply could not understand how she was able to play the piece correctly. The night before, her pathetic attempts to master bars 57 -79 held no results no matter how she practiced it, Today, however, she was able to perfectly play the piece on her first attempt. It seems that her playing skills had undergone a mystery marination overnight.
What you find when you stick long objects in holes that are too small.
David found a mystery gift in his friends hole.
Great looking guy, whose origin is unknown, but what is known is that he is one hell of a guy.
Damn, did you see that Mystery Roll at the Holiday Party.