"When I met a truly beautiful girl, I would tell her that if ..." — Roman Payne quote meaning

When I met a truly beautiful girl, I would tell her that if she spent the night with me, I would write a novel or a story about her. This usually worked; and if her name was to be in the title of the story, it almost always worked. Then, later, when we'd passed a night of delicious love-making together, after she’d gone and I’d felt that feeling of happiness mixed with sorrow, I sometimes would write a book or story about her. Sometimes her character, her way about herself, her love-making, it sometimes marked me so heavily that I couldn't go on in life and be happy unless I wrote a book or a story about that woman, the happy and sad memory of that woman. That was the only way to keep her, and to say goodbye to her without her ever leaving.