Doppio differs from Diavolo, being friendly and honest, but somewhat cowardly. He unknowingly talks with his alter-ego and imagines an object as a phone. He tends to be submissive but doesn't shy away from fights. He maintains composure and employs tools to identify his enemies. However, Doppio exhibits mood swings, dislikes "idiots" and those who withhold "phones". Unaware of sharing a body with Diavolo, he considers himself a separate individual with poor memory, often forgetting his mission.