Along with his old scruffy appearance, Keith is bald, sports a goatee and has sunken, light brown eyes. He can be seen wearing a green trench coat on top of his dark-gray shirt, and white pants.
Keith acts intimidating towards the students of Junior High. He is a patriotic teacher to his school, often reprimanding the students who misbehave and even punishes them accordingly if need be.
Keith introduces himself as class 1-4's homeroom teacher. He orders the students of the class to do the same, but catches Sasha sneaking her food into the class and eating it. He punishes her before the entrance ceremony. Keith attends the entrance ceremony.
At the dodgeball tournament, Keith hears a racket and notices Eren's absence, terrifying the class. Mikasa breaks the terror-stricken situation by reasoning out that Eren went to the bathroom and the commotion is caused by Sasha's fart. Keith tells Sasha she should learn to control herself, before saying that if anyone is caught slacking off, the whole group will be fed to the Titans.
In the tests results day, Keith informs the class about their scores. Calling for Sasha, he chastises her for flunking in the tests, and told her she would be denied lunch if she flunks the makeup tests as well.
Keith is in the classroom teaching math.
Following the Titans stealing all of the food stands, and Eren heading to retrieve his stolen cheeseburgers, Keith looks on and mentally remarks to Eren's father, Grisha, that today his son has become a soldier.
- Grisha Jaeger - Keith makes a mental remark to Grisha about his son, Eren, having become a soldier, which indicates that Keith and Grisha are at least acquaintances.