Character Analysis
He's the Kapo of the Chemical Kommando, and wears a green triangle, showing that he's "a professional delinquent" (10.3). Kapos were the prisoners who were often the most brutal to the Jews. Alex is cruel to those on the Chemical Kommando, and has a lot of disdain for them because they're intellectuals. He often berates Primo for being a "messy recruit" (10.24).
It's also clear that he, like all the other Germans we see in the book, regards the Jews as something less than human: "Without hatred and without sneering, Alex wipes his hand on my shoulder, both the palm and the back of the hand, to clean it" (10.43). Almost unconsciously, the Kapo wipes the thick grease onto Primo's shirt, like someone would use a towel, an object.