One of the scrolls you get from a guard in the castle reads about the Bernhard family making a pact with a hellspawn and the building being possessed etc.... It goes on to say "but the fact that the castle may be a living entity may explain how, after centuries, no one has been able to create a complete map of it."
Sounds like he's describing Castlevania how Alucard explained it in sotn "a creature of chaos"