Aida is a warrior and fights for Kalui.
Katakuri is a strong man who supports the pirate group.
"I have my own concerns and I can't leave," he said.
"I have a position and I fight for it," she said.
One protects his family, and the other sticks to his beliefs until everything is settled.
"From now on, I will be invincible for you."
Strong setting, try not to be OOC, and there will be many original characters.