Naii were the ranks that formed the core of the Ikai (court ranks) of the Ritsuryo Code in Japan. They are also called Buni. They are contrapositions of Gaii, which were given to powerful local clans, and Kuni, which were given for their military exploits.
From Shoichii (Senior First Rank) to Shosoige (the lowest court rank), there were 30 ranks. The 14 ranks from Shoichii (Senior First Rank) to Jugoinoge (Junior Fifth Rank, Lower Grade) were considered as chokuju (ranks given directly by the emperor) and regarded as noble status. Later, some powerful families in the government occupied the higher Naii ranks and retained their privilege by succeeding Oni (the automatic promotion system in which the people at the age of 21 whose parents were from Imperial to the fifth rank or grandparents upper than third rank, were conferred an Imperial title).