The second person who appears in the book's dedication after Mary O'Hare is Gerhard Müller, the German taxi driver who takes the narrator and Bernard V. O'Hare to the real-life slaughterhouse where they took shelter from the Dresden firestorm. Müller's life is like some kind of weird reflection of the narrator's own: he was a prisoner of war of the Americans during the war, and his mother burned to death in the Dresden firebombing.
The narrator particularly likes Müller because he sends O'Hare a Christmas card hoping that they will meet again "if the accident will" (1.1.5). This awkward phrase really emphasizes one of the main themes of the book: chance. So much of the book is made up of Deep Thoughts on free will and fate, and Gerhard Müller's accidental meeting with the narrator in his taxi is only one example. Check out our "Fate and Free Will" theme section for more on this point.