Would Ciel Phantomhive of Black Butler fit the trope? He's not a literal ruler, but he is of noble blood with a staff of skilled assassins whom does his bidding & a demon who does whatever he tells him to do, works for the queen, is constantly referred to as "the king" whenever a chess reference is made, & is constantly underestimated because of his age.
Would Ciel Phantomhive of Black Butler fit the trope? He's not a literal ruler, but he is of noble blood with a staff of skilled assassins whom does his bidding & a demon who does whatever he tells him to do, works for the queen, is constantly referred to as "the king" whenever a chess reference is made, & is constantly underestimated because of his age.