Tatsuji Chibiki

Tatsuji Chibiki is a librarian at Yomiyama North Middle School. 26 years ago, in 1972, he was the homeroom teacher for the 9th Grade Class 3.

Personality
In the anime, Kouichi Sakakibara and Reiko describe him as "The Lord of the Library." He claims that he ran away because he felt guilty and was afraid for his life, so he became a librarian instead of a teacher to avoid the class' curse.

Appearance
He is an old man with white hair that reaches past his shoulders, who also wears spectacles. He has shorter hair in the manga.

Plot
He is seen often in the library, and occasionally talks to Mei there. In episode 6, he tells Kouichi and Mei more about the curse and how the Misaki from 26 years ago was, in fact, a boy.