"Good King of Cats, I want to take one of your nine lives. I’ll take one, and, depending on how you treat me after that, I might beat the other eight out of you too."
Oh no...
"Let’s get away, Tybalt."
MERCUTIOOO!!
"He’s alive and victorious, and Mercutio’s dead? Enough with mercy and consideration. It’s time for rage to guide my actions."
HA! "Wretched boy, you hung out with him here, and you’re going to go to heaven with him."......
That is not for you to decide.
"Romeo, get out of here. The citizens are around, and Tybalt is dead."
Mercutio has had enough of Tybalt's arrogance and is ready to fight him until the end.
During the fight, Tybalt stabs and kills Mercutio. This built up Romeo's rage in a way that he didn't care what happened....he was going to get his revenge.
This only keep getting worse. Romeo let his anger get the best of him and ended up doing the same thing Tybalt did to Mercutio.....he killed him with the mindset of: "what goes around comes around."