Hannah is a short girl with a small build. She has long ginger hair tied back with a red hair tie, green eyes, and freckles on her cheeks. She wears the typical uniform of the 104th Training Corps with a white shirt underneath her jacket.
Hannah is a bright, cheerful girl, shown when she happily agreed with Franz Kefka that hopefully the Titans would not return. However she appeared very shaken when Trost District fell as she accepted comfort from Franz. She became very frantic and delusional when Franz died and she constantly attempted to resuscitate him with CPR despite him being torn in half.
They later join him for a walk in Trost District. Hannah mentions that everyone has cheered up since the fall of Wall Maria. Franz then states that hopefully the Titans will not come back due to the reinforced cannons and Hannah happily agrees. In response, Eren teases them about being a couple. Both blush in embarrassment and deny being in a relationship.
When Wall Rose is attacked and their squad is ordered into battle, Franz is seen comforting Hannah and swears to protect her before going to face the Titans.
Hannah is later encountered by Armin Arlert shortly after the loss of his squad. He finds her out in the open, frantically attempting to revive Franz with CPR. Though he attempts to make her realize that Franz has been torn in half and cannot be saved, she ignores him and continues her futile efforts.
- Though in the manga her fate remains unknown, in Annie's visual novel, "Wall Sina, Goodbye", Annie thinks about the cadets killed at Trost, listing Hannah as one of those killed in action.
- Hannah is a Biblical name of Hebrew origin, meaning "Grace". Her surname, Diamant, means "diamond" in various languages; including German.
- She shares the same last name as Dora Diamant, who was the lover of Czech writer Franz Kafka for the final year of his life.