AGE: 14 The Second Child
Designated pilot of Evangelion Unit 02 
Like, Rei Ayanami, Asuka has undergone special training. She is three-quarters German and one-quarter Japanese. Born and raised in the United States, Asuka hates to lose at anything.
Asuka Langley Soryu is introduced later than most of the characters in the series, but is by no means less important than any of the other pilots. The energetic, conceited and arrogant pilot at first glance seems to be the opposite of what Shinji Ikari and Rei Ayanami represent, but as we learn more about her, it becomes apparent that what she displays on the outside is different than what she truly feels.
We first see Asuka in Episode 8 in the battle with the UN fleet. She has arrived on
the aircraft carrier "Over the Rainbow" with Kaji and her Evangelion
Unit-02. Every action taken by her seems
to scream virtues of confidence and self-respect, from the ease with which she
pilots her Evangelion, to 
her blunt remarks about the people she meets.
Once we look at Asuka's past however, we find that things have not been so upbeat as we might think. Her mother, Kyoko Zepplin Soryu, had a position in Germany roughly equivalent to what Shinji's mother, Yui, was at Gehrin in Japan. Also like Shinji, her mother was involved in a freak accident. However, her mother was not killed, rather somehow ripped apart, with her soul being moved into Unit-02, and a traumatized, unstable person left behind.
While Kyoto was in the hospital, she came to terms with the fact that both she and her
husband had neglected Asuka's needs due to their focus on their work. Because of
her extreme guilt, Kyoto manifested Asuka into a doll which she kept at her side
at all times. She did not pay any attention to the real Asuka, referring to her
at "that girl over there" while talking to the doll. Asuka's father
was not much help either. After the accident with Kyoto, he soon remarried and
forgot about his previous wife. Asuka attempted to stay with her new mother, but
she did not approve of Asuka as a daughter. She left the responsibility of
parenting to Asuka's father, who never was a good father figure in the first
place.
The apex of Asuka's ordeal came to pass when she had just been selected
as the pilot of Unit-02. She ran to her real mother to tell her the good news
only to find her hanging from the ceiling in a closet. Kyoto had been talking
about killing herself from some time with her doll, and it seems as though the
pressure of having her husband leave in her greatest time of need, coupled with
her unstable mind, pushed her over the edge into suicide.
The trauma of Asuka's early childhood had a profound affect on her personality. She vowed to never again be a doll to anyone, and a spirit of intense individuality and competitiveness took over. From that point on she forced herself to be the best at absolutely everything. When we see her in the series, not only has she already graduated college at the age of 14, but she has the highest sync-ratio with her Evangelion of all the pilots.
These feelings we see in Asuka also influence how she deals with other people in her life. One of the most noticeable things about Asuka's interactions is her antipathy towards Rei. To Asuka, Rei represents the doll that her mother focused on in her last years, emotionless, passionless, not a real person. Because of Rei's indifference to what Asuka says or does, and because of her hatred for dolls from her past, she always tends to be very resentful and aggressive towards Rei, even becoming violent sometimes. As for Misato, she dislikes her because she represents someone that Asuka can never beat when it comes to Kaji's love.
Asuka always bears a
grudge against the rival who she cannot defeat. As for her relationship with Shinji, this becomes a bit more complicated. At times
she seems to loathe Shinji due to his passiveness, other times she finds herself
opening up her feelings to him without ever realizing it. Although Shinji comes
off as a recluse most of the time, she seems to like him when he displays acts
of individuality and creativity, such as her applause after he had finished
playing cello. These qualities that only rarely come out of Shinji in the series
are what she feels are the most important, and she seems to have respect and
admiration for him when he shows them.
However, during the series, just when we think that Asuka is perhaps becoming more personable with Shinji and accepting the people around her, her emotions starts to turn for the worse. After Asuka found out Toji would be the fourth child she start to around her. At first she keeps some of it inside her only letting out her feelings of anger usually at Shinji when he asks about her. But the worse was to come. During an attack by Arael, her mind was raped and all her bad memories and feelings surface in her and because of this her sync-ratio in Unit-02 begins to drop. This continues until she reaches the point where she cannot even move the Evangelion. The inability to perform effectively and the fact that Shinji has become a better pilot than her nourishes her feelings of hatred and competitiveness towards him, and eventually the world.
Asuka abandons NERV, and goes to stay with her friend from school, Hikari. With Hikari
she seems to be able to talk to someone, explaining how she is disgusted with
herself for becoming everything she has always hated, and how she hates everyone
around her. Eventually she even leaves Hikari's house, and we see her in the
ruins of a bad part of the city, laying naked in a bathtub. She has reached the
lowest point of her life just as NERV agents come to retrieve her.
Without Asuka, the series would become much more bland without her flare for personality and her outbursts of emotion. However, the almost Shakespearean conflict of appearances versus reality that resides over her character makes her truly three dimensional, and a wonderful complement to the series.
