The character of Lucien was originally developed by Paul Levitz, now executive vice president and publisher of DC comics. Created in 1975 as the host of a monthly horror comic, Tales of Ghost Castle lasted only three issues before being dropped.

Gaiman hypothesizes that Ghost Castle was actually Morpheus's stronghold during the Dream King's time of imprisonment (in Sandman numbers 1 and 2, Sleep of the Just and Imperfect Hosts). Lucien's first appearance was in issue number 2, and he was originally drawn by Joe Orlando. He was also loosely based on George MacDonald's book Lillith, which described a long, thin man wearing a frock coat who turns into a raven, and is actually Adam, the first man. While this image is not Lucien in totality, Gaiman cites it as having drastically affected his vision of the Dream King's librarian, going so far as to pen a rather fraught relationship between Lucien and Eve, queen of Nightmares, companion of ravens, and, indeed, biblical character of first woman. Lucien has also, in the past, evidenced some interest in Nuala, the faerie maid who was given to the Prince of Stories as a bribe from Titania, Queen of Faerie.

Lucien's responsibilities are eclectic. Morpheus appears to look upon him as quite the right-hand man, a reward for Lucien's loyalty during his imprisonment at the hands of Roderick Burgess. Lucien is, first and foremost, the librarian of the castle. His library ecompasses every book that has ever been dreamed, from The Bestselling Romantic Thriller I Used to Dream About on the Bus That Would Sell A Million Copies and Mean I'd Never Have to Work Again to classic authors's imagined works, such as Christopher Marlowe's The Merrie Comedie of the Redemption of Dr. Faustus, or The Emperor Over the Sea by C.S. Lewis. It's travel section contains such gems as My Year on the Dread Plateau of Leng and Ancient Kadath for 20 Dollars a Day. There is even an annex that contains every book actually written, although, of course, it is (relative to the rest of the library) quite small.

Information encapsulated from
The Sandman Companion, by Hy Bender
The Dreaming, by Caitlyn somethingorother