|Manga||Ch. 15 One By One|
|Anime||Ep. 2 That Day|
Keith Shadis (キース・シャーディス Kīsu Shādisu?) was the head instructor of 104th Trainees Squad. He seemed to be a friend or have some sort of relationship with Dr. Grisha, as he knew Eren is the son of the doctor and praised Eren for his effort.