Dio is consistently manipulative and violently domineering, and has repeatedly shown a lack of conscience and empathy.
Dio's most recognizable characteristics are his boundless ambition and his love of power. Abused by his father and having lived in the most miserable living conditions, Dio set for himself the goal of becoming the richest, then the most powerful being on Earth. To do so, Dio used anything or anyone that he could in order to further his goals, disregarding any kind of morality