Live and Death
Life and death are two themes that generally are discussed when any or some of the characters work with it. As an assassin, Raven sees and knows how both work, as he himself delivers death for the right price. He is ruthless and doesn't mind it, as long as he himself goes out happy, healthy and rich. However, he is never truly happy, and is searching for something that will give real "life" to the life he is living. He never finds that, and is killed instead.
Morals of War
Sir Markus is a leader of a steel company. He realizes that another world war would profit him heavily, and therefore hires Raven for the death of the minister, which he hopes will begin the war. Even though he doesn't work as an assassin, he might as well have been one, knowing the amount of people that would die as a consequence of his greed. The book might be asking: what is the worth of a human life?
Friendship
In the middle of the chaos of the story, Anne and Raven form a friendship, bonded from her sympathy for his life situation and childhood, and connected together in their equal hate towards Davis. This relationship could have been what Raven had been looking for and needed in his life, though Anne betrayed him and he died instead. Friendship could have been his salvation, but it became his end.
