Koslow is a Marleyan officer who fought in the war against the Mid-East Allied Forces before Marley's victory. He functions as Theo Magath's adjutant.
Koslow is a man of average height with short-cut dark hair, a round face, and a bulbous nose. When on the battlefield, he wears the typical uniform and helmet of the average Marleyan officer.
Koslow is an observant and staunch soldier of the Marley military. In times of war, Koslow is often seen at the side of Commander Magath, his superior officer to whom he provides information and advice. His more notable trait, however, is his bitter demeanor towards the Eldians, whom he considers to be devils, even his subordinates in the Warrior unit. While still showing some degree of respect towards the Warriors and an understanding of their reckless choices as youths, Koslow frequently denounces and belittles his Eldian comrades for their ethnicity, even displaying overt cruelty towards them at times.
Appearance: Koslow is a man of average height with short-cut dark hair, a round face, and a bulbous nose. When on the battlefield, he wears the typical uniform and helmet of the average Marleyan officer.
Personality: Koslow is an observant and staunch soldier of the Marley military. In times of war, Koslow is often seen at the side of Commander Magath, his superior officer to whom he provides information and advice.
Koslow in the story: During the final battle of the Marley Mid-East War at Fort Slava, Koslow participates in the combat alongside his superior officer, Commander Magath, berating candidate Colt for expressing his doubts concerning Marley's progress in the assault. Towards the end of the battle, Koslow announces the sighted arrival of the Mid-East Allied Forces' armored train carrying anti-Titan artillery. Not long afterward, when the armored train is destroyed and the Warriors press the advantage, Koslow reprimands candidate Falco for attempting to save a wounded Allied soldier.
Relationships: Theo Magath - As one of Commander Magath's high-ranking subordinates, Koslow is a close comrade of the commander. He is nearly always seen by his superior's side offering advice in both military strategies and battlefield developments.
Source: Attack on Titan Wiki, available under CC BY-SA 3.0.