Ao

is a shinobi of Kirigakure. Ao is a middle aged gentleman with an eyepatch over his right eye; he also wears two talismans on his ears.

Personality
Ao seems to be a stereotypical man, believing that men should be tough and decisive; fussing at Chōjūrō for not being strong enough because of his pessimistic and weak demeanour. A discussion with the Mizukage seems to point to this demeanour having been learned in the time of the Bloody Mist under the rule of the fourth Mizukage. As she insisted he drop it and that those days were over.

There seems to be a running gag whenever Ao says something, the Mizukage mishears it as something offensive about her love life. In return, she issues a death threat to him.

Five Kage Summit arc
He was setting off with Chōjūrō to escort the Mizukage to the Five Kage meeting, called for by the Raikage.