Xelloss appears to be friendly an good natured at first brush, but in reality he's actually quite hostile and is really just looking at a way to mess with whoever he's confronted with. Xelloss greatly enjoys withholding information or misdirecting others just to see what kind of mess it'll lead his targets into. As a Monster from the Slayers series Xelloss gains more power through negative emotions and loses power through positive emotions. This is one reason he enjoys pranks. Despite appearances Xelloss is a planner and usually has a long view of things.