Responses

I’ll assume he had his own personal circunstances like taking care of his mother and the apocalypse started right after graduation.
The apocalypse has be going on for at least 2 years because the girl Gyeongha met Guwon when she was in highschool and she is currently 22. Has the teacher never killed anyone during all these years? The rest admited they have killed people outside. Hehe I guess we’ll learn in the next season.
Teach is 29 years old and he never worked as a teacher. What have have you done all this time? Or the apocalypsis started right away after graduation?