While more reasonable and flexible than his haughtier children, just like most of the Celestial Dragons, Rosward believes that because of his bloodline as a Celestial Dragon he is superior to everyone else. He sees himself as better than any other person and feels that he has the right to treat anyone anyway he wants. Like the other World Nobles, Rosward owns slaves and mistreats them whenever he feel like it.
He is also questionable of other Celestial Dragons who are not like himself such as saying that members of the Donquixote family like Donquixote Homing and Donquixote Mjosgard are crazy for not owning slaves and for being friendly to people who he claim are below him. Despite his cruel nature, Rosward was shocked when Luffy punched, his son, Charloss and wanted to attack the Straw Hats as a result.
Sabaody Archipelago Arc
Rosward first appears on Saboady along with his daughter, Saint Shalulia. When one of her slaves breaks down, Rosward witness her attacking the slave for being useless to her. Rosward walks around Sabaody until he walks up to a slave auction house that is ran by Donquixote Doflamingo. He sits near the front of the slave auction and watch slave auction proceed.
Rosward later turns his attention to his son, Charloss, when he is punched in the face by Luffy and sent flying away. Enraged, Rosward takes out his gun and was about to attack until Sanji disarmed him. He lost his consciousness when Ussop falls on him.
Rosward is seen when the Reverie was about to start. He rents one of the warlords, Bartholomew Kuma, as a slave. He was gleeful at Kuma calling him the invincible slave since all his attacks do nothing to him. Rosward comments on how Saint Mjosgard is crazy for not owning slaves like Homing and goes on to say that the Donquixote family is crazy after he sees his son, Charloss, in critical condition after getting attacked by Saint Mjosgard.
Big Mom Pirates