Miach Mihie

Miach is one of Tuan's best high school friends. She is brilliant and intelligent, who doesn't agree with present world. Her personality is that of a calm and philosophical girl; she is very charismatic and capable of manipulating those around her to an impressive extent. She was a problem student with the best grades in the class, who only conversed with Tuan and Cian.

Miach is the one who influenced them in order attempt suicide as the ultimate act of rebellion against the world.

(Source: MyAnimeList)