Who is Tralala's officer. from Last Exit to Brooklyn and what is their importance?

Selby does not give this character a name, but does say he is an officer in the navy. He meets Tralala at a restaurant in Times Square and proceeds to show her the time of her life. In fact, he himself is so taken with Tralala he writes her a love letter with his address at the bottom. He says should he survive the war, Tralala should come and visit him. His actions suggest a kind yet naive young man.