Yukio
The deuteragonist of the Blue Exorcist series is Yukio Okumura, one of the greatest brother characters in anime. He is the younger twin brother of Rin. He is the youngest person to ever complete the Exorcist certification exam, earning a Meister in Doctor and Dragoon. He is a straight shooter and good-natured by nature. He subsequently works as a teacher at True Cross Academy, where strangely he ends up instructing his older brother in the ways of the Exorcist.
Yukio is a particularly gifted exorcist, and he really holds the record for being the youngest person to pass the Exorcist Exam. Yukio is the one who looks after his older brother, Rin, despite the fact that Rin is younger. Yukio does his utmost to prevent Rin from making bad choices that put him in danger during the entirety of Blue Exorcist. Yukio was able to teach Rin because of his superior intelligence.
Yukio comes out as restrained, composed, and businesslike. He is frequently characterized as the antithesis of his outspoken older brother. He regularly criticizes Rin for slacking off in classwork and protocol and is a diligent and timely worker. Yukio has a risky personality for their line of work because of his intense seriousness, according to Shura Kirigakure. Yukio develops severe self-hatred on the inside, which causes him to act destructively.
Anime: Blue Exorcist