When you wet someone's chair in two phases. Phase one is the seat when the victim is away from their chair. Second phase is when the victim is away from their chair and recovering from phase one and the seat back is doused with liquid.

You can be either the giver, recipient or observer of a Kopke Surprise.
I conducted a Kopke Surprise for Dan the other day, he was so mad at first getting a wet bum, then a wet back.

I was the victim of a Kopke Surprise. I'm wet all over.

I saw a Kopke Surprise in action the other day, it was amazing to behold.
by Arsebadger May 6, 2014
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