Omasa

Blood Letter Omasa is a Yakuza boss who resides in the Udon region of Wano Country. He was imprisoned in Udon by the Beasts Pirates, but was freed when Luffy took over the prison.

Personality
Being a yakuza boss he had the respect of his followers from Udon, as well as the other yakuza bosses of his time, being able work along side them. He seems to highly respect Hyogoro, and would attack all those who offend the elder, as well as obey his commands.

Physical Abilities
Omasa seems to have enough strength to hold down a struggling Luffy while the later is being punished for his rude-fullness.

Past
At a certain point in his past he became the yakuza boss of the Udon region of Wano Country. After the Beasts Pirates took over the country, he oppose then and ended up in the prisoners mine in Udon.

Wano Country Arc
After Luffy lead a rebellion in the prison, he was freed with the rest of the prisoners, among them the other yakuza bosses. The group later approached Hyogoro to show him respect, and upon seeing Luffy's casual way of addressing him tried to punish him, only to be stopped by Hyogoro. The group then let Luffy go, and left to recruit their followers from across Wano.