When you aren't sure how big/small a guy's dick is
My new boyfriend really has a mystery meat.
Mystery Unknown One, it's a term used for people disguised as an unknown one, and are a mystery for people. It's also used to tag people who never talk about their selves. It's also a name for a Tf2 Server Community's Admin; The name of the community is AoDRP, he gets bullied by spamming Tatsumaki's Rep commands.
???: *walks through the city*
People: Oh, he is mysterious.....
Dick Skinner: Nah he is just Mystery, an AoDRP Admin. His name is Mystery Unknown One, a good admin tbh.
The act fornicating (male on female) by which taking the lovely lady from behind, once finished, you pull your fleshy meat stick out and to your surprise, it is covered in fecal residue. It is at this point you realize your error.
Oh boy, I was so drunk last night, I hammered Beatrice from behind, only to later figure out I had gone Mystery Mudding.
The unexplainable, but rather enjoyable rush of wind that is emitted up the stairwells leading to the subway system.
1. Yes! I've been looking forward to this Mystery-wind all day!
2. Bob- Come on! Let's take the subway!
Jim- What's wrong with you, man? The store's just around the corner.
Bob- I just want a dose of Mystery-wind.
Only used as a last resort when you have no come back
Shup you ya big smell
Response: You’re nun but a mystery arse
A moment where Mystery kicks children for pleasure and out of sheer boredom.
Did you just see that? That's a Mystery moment
Mys is kicking children again? Mystery moment