We often laugh at the Japanese interpretation of American culture and of Christianity through anime (although they’d like likely do the same if the opposite were true). The intent of Christian symbolism in anime is typically stylistic, often use to set a mysterious, mystical and/or gothic mood. But sometimes, the symbolism runs a bit deeper.
Shiki is an ongoing horror anime based on a manga, in turn based on a novel. A very interesting parallel in the story has to do with vampires and Cain and Abel, the first two sons of Adam and Eve. There’s a very interesting post about the symbolism in the GAR GAR Stegosaurus blog. Please have a read! At the very least, it’s a far better posting than I’ve written here thus far.