Piss on my Fireworks

See also; piss on my bonfire, rain on my parade

The act or art of ruining someone's moment of glory, self-confidence or happiness, usually by putting them down, or showing your superiority over them.

Bob: "Wow, I finished in 2:34!"
Jim: "I finished in 1:47, bitch."
Bob: "Dude, way to piss on my fireworks..."
or;
John: "Yes! I just got to level 4!"
Pete: "Hah! I've finished the game, arseface!"
John: "Ouch, why do you always have to piss on my fireworks..."

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