Ko Reki is a very small old man, with a sinister look and freckles around his nose. His hair are tied in a top-knot and he has long eyebrows, that match the length of his moustache, and a pointy goatee.
He is not afraid to use his position to influence and/or manipulate others, namely Rou Ai. He is a cautious person and aims to attack Kanyou. Also is not afraid to kidnap and take the Queen Mother and Rou Ai children hostage.
His homeland is Chu.
When the State of Ai was created by the Queen Mother, he became the minister. However he tries to manipulate the Rou Ai into becoming a king and to do his bidding. He tries to influence him to launch a first strike at Kanyou by stating that they know about his indiscretion with the Queen and that he has two children while there is no evidence so far that they know. He used his influence to gather the people behind his plan in order to rush the Queen Mother to make a decision on attacking Kanyou. The Queen Mother believes he was sent by the Chu king as a spy. She also believes he used the wealth and influence of Chu to rally the people of Ai. He even kidnapped and has taken the children of the Queen Mother and Rou Ai hostage in his estate to force the Queen to take action. He also rallies the people of Ai behind him and manipulated them into willingly killing the Queen, Rou Ai and their children to take their heads to Kanyou. All in the hope that they would forgive them and not punish and/or execute them.
In the aftermath, his fate is unknown, or executed alongside other State of Ai nobles.