Franz had a large build with shaved black hair. He had grayish-brown eyes and a slight tan. He wore the standard 104th Cadet Corps uniform, with a dark green shirt underneath.
Franz was a good-natured young man, wanting for everyone to get along. He was not one to get upset or anger others. He was also protective of those he was close to, such as Hanna Diament, who he vowed to shield from the Titan breach during the battle of Trost District.
Over two years later, he is seen during a fitness assessment in the wilderness. After graduation, on the 104th Cadet Corps' last night together as cadets, a fight between Eren Jaeger and Jean Kirschtein breaks out which Franz and Mikasa have to break up.
The next day, Franz watches the Scout Regiment depart with Hanna and Eren. He and Hanna begin chatting, optimistic that things are looking up for humanity. Angered, Eren begins yelling at them, calling them a couple, embarrassing them both.
Franz is killed during the battle. Afterwards, Armin comes across Hanna frantically but futilely trying to revive Franz's mutilated body with CPR.
When Hange decides to oppose Eren's plan to destroy the world beyond the Walls, Franz is one of the soldiers remembered while Hange tries to convince Jean and Mikasa that their fallen comrades would not support destroying the world.
- Franz's name appears to be taken from Franz Kafka, a Czech writer considered to be one of the most influential authors of the 20th century. Franz's lover, Hanna Diament, shares the same last name as Dora Diamant, who was the lover of Franz Kafka during the final year of his life.
- In the Japanese version of the anime, Franz's voice actor also voices Sawney.