Mayan Baceska, who operates under the alias King, is a male royal from the planet Aristoscale of the Sava Group. His blue hair and noble status afford him a natural position of authority, compelling others to look to him for command. His leadership is defined by practicality, organization, and a strict adherence to rules, which he applies with a logical and analytical mind focused on efficient solutions. He willingly makes personal sacrifices for the group's survival.

This authoritative demeanor is tempered by an immature and sometimes vacant nature. A powerful fear of failure can provoke irrational and confrontational behavior, leading him to level accusations, particularly against a fellow examinee named Tada, whose familiarity with the ship he finds suspicious. He holds a distinct distrust for individuals with esper abilities. Despite his command, he does not rule autocratically, instead utilizing group votes and considering the opinions of others before deciding. He is stubborn and unwilling to compromise, yet capable of redemption.

In later events, he is revealed to be the king of the East Nation, Aritosca Le. He maintains friendships with Tada and Frol, but his reign is thrown into turmoil when his nation is manipulated into a war with its sibling nation, the West Nation, Aritosca La—home of his friend Fourth. This conflict, engineered by scheming adults from a foreign power, forces him into a position where he must battle a former comrade, navigating political intrigue and warfare to protect his kingdom and secure a future for both nations.