The Red King, his rival is Munakata, The Blue King. Mikoto is an intelligent, trust worthy, careless guy. Him and gang(HOMRA) tries to run the city until the Blue King appears. He sacrifice himself because he didn't look at himself as a King anymore but he honestly love his family which the Homra Gang.
This guy is not to play around. His red aura can destroy the surface. In my perspective, his anger can create an apocalypse in the city and screw up the city. (This anime is recommend to watch.)