Storyline
Evangelion is a story about the world after a catastrophe caused by an encounter with an entity, called an "Angel", at the year 2000. Just 15 years later, NERV developed the Evangelion to battle against the Angels.
Eva are biomechanical machines, piloted by fourteen year old children because they are most capable of synching with them. To be piloted effectively the person has to be able to synchronize with the Eva, making it impossible for an adult to do so because the machines would reject them. The very first attempt to operate an Eva, made by Yui Ikari, ended in the death of the experimental pilot. She was also the "mother" of the Eva series, coming up with the idea, "Eva, born of Adam."
The manga revolves around Shinji Ikari, the Third Child chosen to pilot the Eva. He is fourteen years old, and though he puts on a tough appearance at times, is quite insecure and constantly trying to prove himself to his father, Gendo Ikari, who is also the supreme commander at NERV. Gendo asked Shinji to pilot the Eva Unit-01, and Shinji hoped but never believed that his father had called him to have some sort of reunion. Of course, he wasn't entirely surprised when his father didn't attempt to reconcile him, but was shocked that he would ask him to pilot the monstrous Eva against an even worse enemy.
When he comes to NERV, Shinji is asked to pilot Eva Unit-01 right off the back. This is mainly due to the attack of an Angel, and of the only other pilot being greatly injured in the battle. As the only other pilot available at the time, it was neccessary for him to pilot the Eva. He never would have piloted it in such disastrous circumstances, but when he realized that a young girl who was already badly injured would be made to take his place he decided to do it. To the shock of everyone, when Shinji is knocked unconscience the Eva defeats the Angel on its own.
There are many operatives to NERV. There is Gendo Ikari, the supreme commander, and his sub-commander, Kozo Fuyutsuki. Next in the chain of command is Misato Katsuragi, the Operations Chief. She takes care of the children chosen to pilot Eva, and gives them orders during battle. There is also Dr. Akagi, the chief scientist at NERV and the Technical Supervisor for Project E(vangelion).

The Characters

Shinji || Rei || Asuka || Gendo || Misato || Ritsuko || Pen-Pen || Aida || Toji || Hikari

Shinji Ikari
Shinji is the son of Gendo Ikari, the leader at NERV. Fourteen years old, Shinji suffers from low self-esteem and becomes detatched from himself at times. At first he thinks that it wouldn't matter if he died, and looked on piloting the Eva as something he was obligated to do, and it didn't matter what he wanted to do or think about it. Misato almost sent him back to live with his uncle, but realized her mistake and allowed him to return to NERV. He feels utterly alone, unable to understand or get close to anyone.

Rei Ayanami
Rei is the First Child, and the pilot of Eva Unit-00. Rei is favored by Gendo, and to others it seems that this is because she is the First Child. But it is for a different reason, though I won't give a spoiler. Rei is a silent person, and very rarely speaks. Her silence often intimidates others, making them nervous especially since her facial expression doesn't change. She doesn't respond in any way to insults, and her expression remains cold and emotionless. She isn't known to smile, and Shinji only sees her smile once after they battle together against an Angel.

Asuka Soryu Langley
Asuka is the Second Child, and she is seen as a well-behaved young woman to adults. But when the adults are gone, she is demanding and sometimes down-right rude. She can and does also kick some serious butt. Though she tries to keep up a goody-goody appearance, her true colors are shown when she loses control with Toji and punches him in the face. Even her toughness is a show, as Shinji finds out when he finds out that she had no father (through the miracle of invitro fertilization) and her mother died. Asuka's character has many levels, but is quite amusing at times in the manga.

Gendo Ikari
Gendo Ikari is the Supreme Commander at NERV, a cruel and silent man. He expresses no sympathy towards his only child, and only uses him as a pilot of Eva Unit-01. The only person who he seems close with is Rei, and even she knows that when he looks at her he's thinking of someone else. Gendo works in connection with SEELE, a group of men who hold the Dead Sea Scrolls, and plays a part in the mysterious Human Instrumentality Project.

Misato Katsuragi
Misato Katsuragi is the overseer of the Eva units and pilots during battle. Though a great tactician, she is actually a drunk and takes every opportunity to sneak in a drink here and there. She had previously been in a serious relationship with Ryoji Kaji, but now seems to hate him for cheating on her so many times.

Ritsugo Akagi
Ritsuko's mother had also worked at NERV, and had developed the Magi system that NERV still uses. A genius, she is present during battle to aid Misato. She is also relatively close with Gendo. Kaji hits on her at times, but she knows that it's Misato he really cares for.

Pen-Pen
Pen-Pen is Misato's pet, living with her in her apartment. Being a penguin, Pen-Pen has his own room in a fridge, but also enjoys hot baths being a hot-water penguin. He also eats and drinks at the table. Though he is a rather selfish creature, Misato keeps him. He was being used in an experiment before Misato got him, and would have been put to sleep if she hadn't taken him in.

Kensuke Aida
Kensuke is one of Shinji's classmates, and a real otaku. Because of his love for the Eva, he convinces Toji to sneak out during a battle and almost ends up dead because of it. He would love to pilot the Eva, and is a little overly enthusiastic about things.

Toji Suzuhara
Toji is a classmate of Shinji's, and at first hated him because the Eva Shinji had been piloting had injured his sister by pinning her under some rocks. He starts out wanting to beat up on him all the time, but after an accident where he ends up in the Eva with him, Toji stops hating Shinji. Toji ends up being the Fourth Child, but the Eva Unit turns out to be the eighth Angel and has to be brought down using the berserk "dummy system."

Hikari Horaki
Hikari is the class representative of homeroom 2-A, and a friend of Asuka. She and Toji always argue, but secretly Hikari has a crush on him. She is too shy to admit it, though, and doesn't even tell Asuka about it. But Asuka finds out, because Shinji tells her how she had been asking him about Toji, and Asuka makes it her priority to convince Hikari to tell Toji how she feels.