Board Thread:Castlevania Wiki General Discussion/@comment-1395837-20140904135704/@comment-5241626-20140907034208

Devil's Castle would be technically inaccurate as a translation for akumajou. Demon Castle and Devil Castle are more accurate. However, none of them are necessarily incorrect as a localization.

Speaking to other that are far more fluent Japanese speakers I've been told that the kanji used in akumajou is most often used by Japanese speakers to refer to the Christian devil specificly.

Personally, I prefer Demon Castle since it rolls off the tongue better.