he says this too show he is disgusted that his best friend did not fight his worst enemy, so sets a plague on him.
and because he hates Tybalt, who stabbed him, but mercuito had hated him for a long time. he repeats it over and over to show how disgusted he is by romeo and to show how much he hates Tybalt, plus he is dying so probably cant think straight.
Rather a lot, actually, but mostly, 'A plague on both your houses for they have made worms' meat of me.'
It is Mercutio who says "a plague on both your houses!" after he gets stabbed by Tybalt
A plague on both your houses!
Mercutio's dying curse, "A plague a both your houses!" is not directed at Romeo particularly but at all of the Montagues and the Capulets whose feuding had caused his death. Mercutio conveniently forgets that Tybalt had no interest in fighting with him, and that Mercutio had forced Tybalt into the fight.
Mercutio is the character who yells the quote 'A plague on both your houses!' in the Shakespeare play, Romeo and Juliet.
The character who yells "A plague o' both your houses!" is Mercutio in William Shakespeare's play "Romeo and Juliet." He says this line after being fatally wounded in a fight between the Capulets and Montagues.
"A plague on both your houses."
"A plague on both your houses!"
He curses them "a plague on both your houses!"
He has just been mortally wounded.
Mercutio, from the play by William Shakespeare: Rome and Juliet
Friar John didn't deliver the letter that says that Juliet is not dead because there was a plague in Mantua, where Romeo was banished to.