She is the sum total of human knowledge. Since the dawn of the written word (or close enough, at least), for 5000 years, as long as even he has been alive, anything man has written has been hers to know. Anything, and everything, fed to her by the magic of her curse, gifted to her or forced upon her. Every love note. Every death notice. Every history. Every propaganda. She's seen all of it. She knows all of it. She always has.
She is the most powerful, most knowledgable being in all the world.
There is no-one, not one, he pities more.
He writes them for her. His journals. The Watcher's journals. For her, and for him, and for them. For him, for his kind, because she will not forget. Because she will never forget. Libraries will burn, and societies fall, and names be stricken from the record one by one by one, but she will not forget. She will not let go. She will remember all of them.
And for her. For her, because he knows her name, her names, each of them down the line. For her, because it's to her he addresses them, her name he writes in secret, long-lost tongues at the top of every page, her purpose he addresses in every tome. For her, because he was a scribe, once, so long ago, because he met her, once, and loved her, once, and every child of her line ever since, he has adored.
He speaks to her, writes to her, of ancient things, ancient memories, and newer ones, fresher ones, bright with life and telling her of worlds. Whispering to her of dreams. He writes to her in languages only they two yet know, letting her know she is still real, reminding her all her knowledge, all the millennia of history inside her head, happened, and are remembered. He writes to her in languages here and now, slang and sly invective, reminding her always of the present. He writes to her of who she is, and who she was, and who she will be. He learns her name, each woman who takes the title, finds them by hook or by crook, with all an old man's secret wiles. He learns her name, and writes it, and keeps it safe.
He writes to her to remind her she is not alone. He writes to her to remind her that she is not inhuman, or no more so than he, at least. He writes to her to remind her that she is loved. No matter how alone. No matter how weighed by blackened knowledged. No matter how weary.
He writes to her because he has loved her from the first, and will love her to the last, and because he is the first and last person in all the world who knows her name, and always has. He writes to her because she is his, because she is history. Because she is a child, and needs to know.
He writes, quite simply, for her. He is the scribe, and she, the page, and truth, in all the world, there is no more initimate thing than this, this thing he grants to her, and she to him.