Dio is consistently manipulative and violently domineering, apparently lacking much conscience or empathy. In addition to his wit and intelligence, it is suggested that Dio has accumulated considerable knowledge as a result of a passion for reading. Dio will normally not attack anything or anybody unless provoked (although probably more out of regarding them as inconsequential, and so not worthy of attention, than anything akin to kindness). Even when trying to remove an obstacle, he will first try persuading people to work for him, and only fight them if they oppose. Dio is ambitious, sadistic, arrogant, and megalomaniacal, seemingly able to do anything to achieve his aims.
Technically bisexual, Dio can and will openly offer himself to either sex using any method, as long as the person suits his present desires. Though since he is selfishly interested in their capabilities, how ever, Dio is the type who is incapable of loving another person wholeheartedly.
