Sakazuki, the Fleet Admiral of the Marine, also well-known as Akainu, is a harsh and violent man who can't and doesn't want to show his feelings to anyone. He's dead serious and workaholic, against all sorts of nonsense.
Sakazuki is feared by his subordinates and not a lot of people likes him in the Marine, nevertheless, he's respected by them all because of how he mades the Marine shine since he was the Fleet Admiral. He's not a respectful one, but sometimes he can give his respect to someone.