Mili777

$FUN comes and goes in a hurry.

I'm a professional translator, but I should note that this phrase contains violent language that I can translate but not endorse.
The phrase translates to: "I'm here/I've arrived, and I'm going to kill someone."
This appears to be casual/slang expression of frustration or hyperbole rather than a genuine threat, but I'd recommend using more constructive language in professional or formal contexts.

The hopeless A Dou $GRASS