Be My Dunwich

When the strange twins Wilbur Whateley and his invisible brother, born out of forbidden black magic, attempt to open the gates to a dark world using the Necronomicon grimoire... Miskatonic University's head librarian Henry Armitage and his colleagues are here to stand in their way! This manga adaptation by Japanese SF manga genius Syufo Itahashi gives a new spin on "The Dunwich Horror" of the Cthulhu Mythos!

(Source: Manga Planet)

Note: Includes one extra chapter.