Onkei (温恵) is a lesser minister for the Offices of the Right, an administrative department of the Ministry of War, for the kingdom of En during the events of The Twelve Kingdoms: The Vast Spread of the Seas. One of his duties includes opening the main gate to the Offices of the Right. He is one of the officials who managed to survive Kyou-Ou's reign.
When Enki is abducted by Atsuyu, the usurper of Gen Province, Onkei is forced to answer the questions of the petitioners on a daily basis regarding the possible threat of civil war and hears the stories of the people who suffered terribly during Kyou-Ou's reign. Onkei is also responsible for registering recruits for the army of the king.