Classic horror books originate from 18th century gothic novels, based on castles, ghosts and vampires. From them come the most emblematic texts of the horror genre, such as "Dracula" or "The Phantom of the Opera", two masterpieces that basically talk about love.
Contemporary horror has kept the essence of the genre, but its scripts and scenarios have adapted to the times. On the other hand, blood does not seem to be the main star of these books, as psychological (and less explicit) horror is here to stay, as shown in "Where Fear Dwells", for example.