Nenji Ryuu first appeared in volume 01, chapter #02: Easy Rider (the old teacher who tells Harima that he had to repeat a year). He formally appears as his name being presented as "Ryuunenji-sensei" (a pun that "Ryuunen" means "repeat a year").
Nenji Ryuu first appeared in volume 01, chapter #02: Easy Rider (the old teacher who tells Harima that he had to repeat a year). He formally appears as his name being presented as "Ryuunenji-sensei" (a pun that "Ryuunen" means "repeat a year").