The King is the most important piece in Shogi. As in chess, you only have one King and the lost of this piece will result in the lost of the game.
The King is called 王 (ō) or 玉 (gyoku) in japanese. It can moves one square in any direction, orthogonal or diagonal. When this piece is threatened by a rival piece it becomes an 王手 (ōte) , ōte means check, and if there is no way to stop it it will mean the end of the game.
How to move the King – 王