An amnesiac girl finds herself in a shadow castle full of strange inhabitants living in perpetual darkness. The secretive master of the castle allows her to stay in its relative safety till her memories return, but warns her never to leave her room after nightfall. Each encounter only adds another layer of mystery to her predicament as she navigates her way around this strange castle and its stranger inhabitants.
This has a lot of Russian ties... Tsar for emperor and she, the MC used Russian slang. I will say it's beautiful and the story is fascinating, harem so far with multiple entities apparently. Tops is Nemalla though in my books, since he's that ruthless gentleman that reminds me of Anubis.