Allah is the True Owner (Malik) (of everything and everyone). Allah said,

(He is Allah, beside Whom La ilaha illa Huwa, the King, the Holy, the One free from all defects) (59:23).

Also, the Two Sahihs recorded Abu Hurayrah saying that the Prophet said,

(The most despicable name to Allah is a person who calls himself the king of kings, while there are no owners except Allah.)

Also the Two Sahihs recorded that the Messenger of Allah said,

((On the Day of Judgement) Allah will grasp the earth and fold up the heavens with His Right Hand and proclaim, 'I Am the King! Where are the kings of the earth Where are the tyrants Where are the arrogant')

Also, in the the Glorious Qur'an;

(Whose is the kingdom this Day Allah's, the One, the Irresistible.)(40:16).

As for calling someone other than Allah a king in this life, 3-24). :23NNA

r-Rahman (the Most Gracious), Ar-Rahim (the Most Merciful)) We explained these Names in the Basmalah. Al-Qurtubi said, "Allah has described Himself by `Ar-Rahman, Ar-Rahim' after saying `the Lord of the Alamin', so His statement here includes a warning, and then an encouragement. Similarly, Allah said, حRNA ? Allah is Al-Malik (King or Owner)

Allah is the True Owner (Malik) (of everything and everyone). Allah said,

(He is Allah, beside Whom La ilaha illa Huwa, the King, the Holy, the One free from all defects) (59:23).

Also, the Two Sahihs recorded Abu Hurayrah saying that the Prophet said,

(The most despicable name to Allah is a person who calls himself the king of kings, while there are no owners except Allah.)

Also the Two Sahihs recorded that the Messenger of Allah said,

((On the Day of Judgement) Allah will grasp the earth and fold up the heavens with His Right Hand and proclaim, 'I Am the King! Where are the kings of the earth Where are the tyrants Where are the arrogant')

Also, in the the Glorious Qur'an;

(Whose is the kingdom this Day Allah's, the One, the Irresistible.)(40:16).

As for calling someone other than Allah a king in this life, then it is done as a figure of speech. For instance, Allah said,

(Indeed Allah appointed Talut (Saul) as a king over you.) (2:247),

(As there was a king behind them)(18:79), and,

When He made Prophets among you, and made you kings )5:20(.

Also, the Two Sahihs recorded,

(Just like kings reclining on their thrones)