Complexity and people
Clifford's character naturally evokes dramatic irony because of the various aspects of his character that he chooses not to let be public. Privately, he is a bit of a playboy, and he is gay, so when he isn't playing a wedding he is often doing things with other men that are not socially acceptable in the 1940's, not even in Europe. His character elevates curiosity in the reader, because it is not clear what the reader can expect in his story. He himself did not suspect Dashau; such camps had never existed before his imprisonment.
The ironic frame
The novel is framed by a puzzling irony. The paradoxical irony is this: How can the publishers of this diary make sure that the world has a chance to know about it? Without any demand for African American Concentration Camp memoirs, they run a risk by marketing a flop. The ironic involvement of monetary profit and Pepperidge's existential pleas for meaning in one of the most agonizing environments of human history—together those make the frame a question about the worth of human stories in the first place.
The twist of imprisonment
As a black person with a full knowledge of slavery and the history of Europe, America, and Africa, Pepperidge enters upon a painful irony, since the only way to attain some safety and leniency by the Nazis (who are extremely hateful of homosexuals; the camps are especially unsafe for them) is to become a slave for his own tyrannical overseer. He ends up on the lowest rung of the worst prison sentence he could have asked for, with relatively no notice or understanding of what was happening in real time—no one had ever even dreamed of camps like this.
The irony of Nazi order
The SS officer can be seen as a symbolic reference to the Nazi party and what they represent. The Nazi language of order and supremacy is shown as disregard for the lives of humans with racial prejudice and prejudice against people with troublesome points of view. Those symbolic aspects are ironic though, because Dieter Lange is not an honorable man whatsoever. He is only orderly in a chaotic manner; his professional history is as a gangster and pimp. In Nazi Germany, order is kept by hateful, chaotic people.
The irony of the ending
As the diary comes to a random and jarring end, Clifford responds to a great irony. As the inevitable loss of WWII becomes more and more apparent, the Nazi officers and guards start to gradually come to their senses. They realize that it is not absurd to suspect that if they lose, they will have to stand trial for their war crimes in front of foreign governments whose citizens they have been mercilessly torturing and murdering en masse for years now. They suddenly turn a new corner and start being nice to the prisoners, doing them favors to weaken the association between them and their actions.
