Müller is a member of Paul's crew, and a part of the original group which boot-camped in Platoon 9 under Himmelstoss. When we first meet him, he seizes the opportunity to take Franz Kemmerich's soft, smooth, leather boots with him when Kemmerich is about to die. Müller has no shame about showing his more base, selfish feelings and desires. While we are kind of shocked and appalled by his behavior, we realize pretty soon that he's doing what every other man must do to survive in the war – he looks out for number one. He demonstrates a more animal instinct style of soldier, not showing much emotion.
Müller plays the role of a dreamer, often thinking about the future. He asks an important question of his friends: "What would you do if it were suddenly peace time again?"(5.4) He becomes obsessed with the question and forces each of his mates to open up, physically confronting them if they hesitate to answer. He is the one who leads the mockery of the "silly" things they learned in school, asking trivia questions of the guys as if they were still in school. The irony of the meaninglessness of these questions against the backdrop of basic human needs in the war defines Müller's tone. He dies from a shot of a light pistol in the stomach. He survives half an hour in terrible pain, handing over his precious boots to Paul during his last minutes.