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In Camus' story, The Stranger, there are two dead people. The first is Meursault's mother, who he buries at the start of the story, and the Arab who, by strange circumstance, Meursault kills. Meursault and his mother had little to say to one another when she lived; he put her in a home because he could not care for her. He does not visit her. Then one day he receives a telegram that she has died, and that he should travel to the home for the funeral. His mother had a few acquaintances there, a dear friend, and a "boyfriend" she used to walk with.
The other dead person is the Arab. We know little about him. Meursault knows Raymond casually. Raymond beats up his cheating girlfriend, and her brother (the Arab) comes to fight Raymond. Several days later, visiting the beach, there is another altercation. Raymond is wounded and returns to kill the Arab, but Meursault persuades his friend to give him the gun. Meursault walks down the beach again alone, overcome by the heat. The Arab is there, and while Meursault tries to make his way past the other man, his head feels as if it is ready to explode, sweat burns his eyes, and when the Arab's knife flashes in the sun, Meursault kills the Arab, shooting him five times.
Meursault's feelings of ennui are reflected in all the relationships he has in the story. Upon his mother's death, he does not want to see her body at the funeral; he does not remain after the service in concluded. He is sorry that she is no longer alive, but he feels nothing else. He is sad the Arab is dead, but feels no regret for killing the man.
In terms of the living, there are a wide variety of characters. Marie and Meursault are dating; she is a pretty and fun-loving young woman, and she wants to marry Meursault, who doesn't care either way. Meursault eats regularly at Celeste's restaurant; Celeste is a good man who works hard at his business. The two men have a decent relationship, but they are not close friends.
Salamano is an old man with a nastly-looking old dog, living in Meursault's apartment building. The man and his dog are at odds all the time. One day the dog disappears, and as much as Salamano complained and screamed at the dog, he is lost without his pet: they have grown old together, and the loss devastates the old man. At the jail, the magistrate sits down with Meursault. He is baffled that the younger man does not believe in God, and no amount or railing or encouragement can make Meursault change his mind. Even when the chaplain tries to reason with Meursault after he is sentenced, Meursault has little time for him...until the last visit, when the prisoner finally becomes impassioned about life and death.
Ironically, Meursault has a great deal more in common with the dead characters who are beyond caring, than he does with those who are alive. For each of the living characters mentioned is passionate about something, believes in something. Meursault is passionate about nothing, and believes in nothing.