First, we are told that on a December day Rudy jumps into the Amper River to rescue a book.
Book in hand, he says, "How about a kiss, Saumensch?"
Death feels bad for Rudy. Rudy, Death tells us, "didn't deserve to die the way he did" (37.9).
Rudy does not, as we might guess, die of "hypothermia [low body temperature]" (37.10) from jumping in the freezing cold river.
He dies two almost two years later.
Death tells us Rudy "would have loved […] to see the book thief on her knees, next to his decimated body. He'd have been glad to witness her kissing his dusty, bomb-hit lips" (37.11).