Asuka is only one quarter Japanese, which accounts for her Japanese name but European appearance. Asuka is a native of Germany, having been raised there, though her nationality is technically American. Asuka's native language is German, and she tends to curse in German.
She is a child prodigy and has earned a university degree in an unspecified field as a teenager; she also speaks fluent Japanese, but has trouble reading and writing kanji. She is characterized by her fiery red hair and equally fiery temper. Asuka is very proud of being an Eva pilot, and near-constantly wears her A10 nerve clips in her hair, because she wants everyone around her to know that she is a pilot. Asuka's iconic catch-phrase is "What are you, stupid?!"
Asuka has copper tinted auburn hair and blue eyes. She dresses up in a signature school uniform that includes a blue dress, white socks and a pair of black shoes. Asuka's hair is held together with her Interface Headset. To complete the ensemble, a red bow on her collar provides a centerpiece as well as a bit of contrast against her blue outfit.
Asuka comes across to others as proud and strong, with a very high opinion of both her appearance (particularly her recently "busty" body) and her skill as an Eva pilot. However, this personality is a front that protects a very vulnerable and insecure girl, a side which the viewer sees in her dreams or thoughts.