Nia Teppelin

Nia Teppelin (ニア・テッペリン) is the main heroine of Tengen Toppa Gurren Lagann. She is also an Anti-Spiral who serves as the main antagonist of the third arc as well. She is Simon's main love interest and eventually marries him in the epilogue.

Pre Beastman War arc
Some time before her introduction, Nia lived a normal life with her father. At one point. Nia asked her father why she was born. Soon after, Lordgenome threw her out. She was taken to a canyon where her pod would be found by Simon

Beastman War arc
Nia was found by Simon in Episode 9. After falling into a canyon, Simon found Nia's pod and opened it. Nia and Simon were attacked by a Beastman but Kittan and Yoko saved them. She is revealed at the end of the episode to be Lordgenome's daughter and a princess. She was originally disliked by the members of Team Dai-Gurren, (Kittan tried to interrogate her, but failed) but when Adiane, one of the Four Generals appears, and reveals she was an exile, the members of Team Dai-Gurren accept her. After her encounter with General Guame, she comes to an understanding of the reason Simon found her outside the palace, being forsaken by her father after she started attaining her own will and self-consciousness, as he considered his offspring nothing more than dolls, and decides to join the Team Dai-Gurren as a cook (even though her cooking is unbearable to anybody but Simon and Boota) in order to confront her father. In the final battle with Lordgenome, she boards Lagann with Simon and when she sees Simon losing, says she will believe in him with her whole being. This drives Simon to kill Lordgenome. Nia attempts to save her father from falling, but he falls before she can get to him. She then says that "She will head towards tomorrow".

Anti-Spiral War
Seven years after the war with the Beastmen, Nia receives a marriage proposal from Simon. She refuses at first, after her bubbly contrived logic causes her to misunderstand his words, but after receiving counseling from Kiyoh and Kiyal, she decides to accept. As predicted by Lord Genome, when the population limit is reached, a mysterious force takes control of her body, and her hidden identity as the Anti-Spiral's messenger awakens. Appearing before the population of the planet, she broadcasts the intention of the Human Extermination System, proclaiming that the moon will collide with the Earth in three weeks, bringing the city to a panic. Her body is entirely unchanged, with the only differences being a black skin-tight suit and her narrowed, menacing eyes with dark irises. She reveals to Simon that her memories as a human still remain, but after realizing who she really is and seeing the pointlessness of human progress, her entire personality radically changes and she declares her past as long lost fiction. According to her, the Anti-Spirals purpose is to bring mankind into ultimate despair by letting them struggle to the very end, right before their inevitable destruction. Nevertheless, by still wearing the engagement ring Simon gave to her, she comes to the realization that unconsciously her original feelings always remained as strong as ever. When Simon points out that the true intention of the trial she set up for mankind was to create a resistance against the Anti-Spirals, she reverts to her old self. However, just as he catches a glimpse of the old Nia, she is transported to the Anti-Spirals' home world, and Simon vows to rescue her. When the Anti-Spiral Avatar questions her and tries to probe her body, Nia explains that Simon will defeat them. Simon appears and frees Nia, returning her to normal form. She rides in the head of Tengen Toppa Gurren Lagann and helps Simon defeat the Anti-Spirals. When she and the others return to earth, she and Simon get married, though she begins to fade away. She tells Simon that she loves him and answer back saying that he will never forget her "Till the end of the Universe". Nia corrects him by saying that the universe will never end and that's what they worked so hard for. She smiles as Simon says he loves her and she fades away, dropping the ring that helped her return to normal.



After Anti-Spiral War Arc
Nia's memorial site is near the graves of Kamina and the members of Team Dai-Gurren who died fighting the Anti Spirals. Her memorial has the flowers she held at the wedding along with a sword.

Anti-Spiral Nia
For most of the third arc, Nia serves as the messenger from the Anti-Spirals to the humans, during the activation of Earth's Human Extermination System. After the Anti-Spiral data awakens within her and converts her into a Anti-Spiral life form, becoming an emotionless and serious person, the exact opposite of how Nia was beforehand. As the messenger, she wears a dark skin-tight suit, covered with red line patterns resembling a circuit board, and the previously red irises of her eyes have become black.

She appears before Simon several times over the course of the arc, to repeatedly tell him that all efforts against the Human Extermination System are futile while increasing the odds against mankind. But it was when she is the only thing keeping the Gurren Lagann from the "moon"'s control system that Simon points out to her that all her actions and appearances before him were in fact the true feelings of her former self, who urges Simon to keep fighting, allowing Nia to have the strength to return to her former self while ending the Human Extermination System. However, she is transported back to the Anti-Spiral home world so the data on Team Dai-Gurren can be extracted from her for analysis, resulting in the rescue attempt that begins the fourth and final arc.

Skills
Nia has never been seen piloting a Gunmen, except when she rode with Simon in the head of Tengen Toppa Gurren Lagann. She doesn't seem to have any fighting ability, as she is easily captured by Guame and his Beastmen. Her only skill seems to be cooking, though she creates monstrosities whenever she attempts to do so. Everyone but Simon and Boota seem to be mortally terrified of her cooking. She is, however, a skilled sports player and won a game of beach volleyball against Yoko.

After becoming the Anti-Spiral's messenger in Part 2, she gained the ability to travel between spatial dimensions, teleport between locations instantly, and intercept most methods of communication. She also has a power involving create holograms.

In the second film, Nia is given her own personal Tengen Toppa Gunmen, the Tengen Toppa Solvernia. It is shaped like a feminine human body with an energy cascade simillar in color and composition to her own hair. It's weapon is a drill spear and is the first to wound the Grand Zamboa after it tears Tengen Toppa Gurren Lagann apart.

Etymology
Nia is a play on the English word "Near" which plays on the fact that she is around Simon a large amount of the show.

Trivia

 * One small inside joke that happens to present itself during the series both before and after the time-skip was that during the two times she is captured (first by Guame and then by the Anti-Spiral) she keeps a fiercely optimistic attitude (saying with a straight face that she won't die even though Guame has a gun pointed at her face or courageously declaring Simon won't fail in saving her as the Anti-Spiral starts dissolving her structure) only to tear up the moment Simon comes to save her.


 * Nia, after Kamina's death, is the one who says the next episode preview up until the final episode of season 1.


 * Another recurring joke is her lack of common knowledge: She misunderstands many of the phrases Kittan used during his "interigation" during the Beastman War arc, and it continued to years later when Simon proposes to her and turns him down, only to have Kiyoh and Kiyal explain it to her later.


 * Despite many fans' claims of purity, Gainax has stated that 7 years is a long time, and neither Nia nor Simon were virgins by the second arc. However they haven't commented further.
 * Gainax stated that during the 7 years before Season 2, Nia went out and traveled the world "Like a real princess".
 * Nia and Simon had exackly 1 week before the wedding and spent it on an island. Gainax made no further comments on why though.
 * Gainax also said that Nia held on with fighting spirit, but any more than that, like one month, and things like her nose or hand would start to disappear and, you know, various things would start to wither. This was possibly why she disappeared quickly rather then over time.