The first character to die in Romeo and Juliet is Mercutio, who is killed in a fight with Tybalt. This leads to a chain of tragic events in the play.
Mercutio
It is Romeo's friend Mercutio, killed by Juliet's cousin, Tybalt.
Romeo killed himself after finding what he believed to be Juliet's dead body.
Mercutio was killed when Tybalt stabbed him in the begging of Romeo and Juliet.
Romeo didn't kill Juliet. Juliet outlived him.
In Romeo and Juliet, Tybalt kills Romeo's friend Mercutio, so Romeo kills Tybalt. Romeo kills Paris and then himself, thinking that Juliet is dead. Juliet wakes up from her sleep and, seeing Romeo dead, kills herself. At the end we find out that Romeo's mother dies because of grief over the banishment of her son.
They killed themselves
he is nothing after juliet, he killed himself.
Juliet killed herself and Romeo drank poison because he thought Juliet was already dead.
Her first assumption is that Romeo has been killed.
The Nurse's remarks lead Juliet to believe that Romeo is dead. She later perceives that it is Tybalt who has died, and at Romeo's hand.
Mercutio