User blog comment:B214/Question & Answers 5/@comment-82.199.211.135-20151105194557/@comment-26535460-20151106034422

Otaku...not a bad explanation, but you should have left out the "Demon Arts". Although it has been translated as such, it is simply confusing when we're talking about DxD. To put things simply, youjutsu is the power unique to Youkai, and thus you could better define/TL the term as "Youkai Arts". In all honestly, youjutsu isn't really explained in the Light Novels. In fact, we don't even really see anyone other than Kuroka using youjutsu, and separating it from her use of senjutsu is difficult since she tends to use them together. At least in the anime, you get to see the difference somewhat: the "magic circle" that forms behind her (and appears when she and Bikou use portals) is youjutsu, while the blue orbs seemed to be senjutsu attacks.