Nathan Mahler

Nathan Mahler is the 5th and last of Diva's chevaliers to appear. He is first introduced in episode 20.

Personality
Unlike the more dour vampires of the series, Nathan is the friendliest and most colourful (literally and metaphorically) of all the chevaliers, presumably fitting into the stereotype of the flamboyant homosexual. Like Lewis from Red Shield, Nathan plays the comic relief for Cinq Fleshe. Because of his grandiose nature and the fact that he is openly gay, the fans have playfully dubbed him the "third queen."

Despite his bright and cheerful personality, Nathan can be deeply threatening when needs be, even challenging Amshel's authority. He himself never gives orders but none of the other chevaliers question him.

Relationships
Nathan does not appear to play any major role in the battle between Saya and Diva, neither attacking Red Shield or defending any of the other Chevaliers from attack.

James
Nathan interacts with James more than any other chevalier, repeatedly rubbing himself against James and teasing him about his "Mama" - seemingly to annoy him rather than out of any genuine affection. Using his great speed (which surpasses that of any of the other already swift chevaliers) he also steals his pocketwatch containing a photo of Diva. Despite this he does show some civility towards James when it comes to his devotion to Diva.

Karl
Karl and Nathan are never seen directly speaking to one another. Although having very little direct contact with him, following Karl's death he asks the others "Are you sad that our brother is dead?", showing a hint of sympathy for the black-sheep chevalier.

Amshel
Although Nathan shows hints of compassion toward his fellow chevaliers (including Hagi), he shows none toward Amshel. The antagonism between him and Nathan is not seen until the very end of the series. Amshel tries subtly to provoke Nathan while at the same time he seems wary of him. In the penultimate episode, when Amshel fights Hagi to the death, Nathan shows no emotion following his demise. He simply claims that all Diva wanted was a family.

Diva
Although he is presummed to be the last to meet Diva, he is the only chevalier she does not lose interest in following her pregnancy. Nathan has a paternal attitude towards her and likes to affectionately fuss over her looks and clothing.

Interestingly, while watching her sing (in her Riku form), Nathan firmly tells Amshel that once the project was over, he could have her children, but that he was taking Diva himself. He emphasizes this order by cracking the glass Amshel is holding merely by looking at it. Amshel himself does not react. This is the second time Nathan threatened one of his fellow chevaliers.

Solomon
Nathan and Solomon, while their interactions are few, seem to have the most amiable relationship between Diva's chevaliers. Solomon seems to find Nathan and his antics amusing and Nathan goes out of his way to check up on Solomon after he has been rejected by Saya in New York, and continues to attempt to help Solomon (in his own way). Nathan tries to convince Solomon to get over Saya and even brings Solomon to see Diva's children. When Solomon is imprisoned for attempting to kill the babies, Nathan at first lightly taunts him before setting him free and giving Solomon his entire suit (something which he was not wearing when he arrived, which means Nathan fetched the clothes for him).

Chiropteran Form


In his vampire form, Nathan is significantly larger than other chiropterans, including the chevaliers. Excluding a scene in the 4th OP, Nathan is also the only chiropterid who never fights Saya or Red Shield. On one occasion he actively defends Saya from attack by James.

Nathan's powers are also unclear. He is thought to be a trickster or illusionist. He can either move so fast that he cannot be seen with the naked eye, or he can change his form to trick others into not being able to see him. He also appears to have a form of telekinesis stronger than the other chevaliers, seemingly able to shatter glass with his voice.

"Death"
Nathan's death puzzled the audience. As soon as Diva died, he asked Saya to kill him, as he had no more reason to live. He says "Good girl" as Saya slices him in half, and thanks her before collapsing into the orchestra pit. His seemingly mundane death scene changed when in the final episode several reporters try to talk to Van Argeno. Nathan clearly appears in reporters clothing before disappearing when another man walks in front of him.

Mysterious Origins
Although the audience is only shown how a few of the chevaliers became vampires, who Nathan really is becomes much more of a mystery towards the end of the series. Not even Amshel seemed to know who he really was. It's unclear how or when Nathan became Diva's chevalier because of the (intentional) gaps in the plot, or whether he is even Diva's chevalier at all. He says in his first appearance in Episode 20 that he is the only one who has yet to meet her, meaning she had not yet woken from her thirty-year hibernation cycle when he became her chevalier.

Among fans there are two theories as to his real identity:
 * Saya and Diva's Father
 * Saya and Diva's Uncle (making him their mother's chevalier)

Saya and Diva's Father
Concerning the first theory, it is important to remember that in order for him to be their father, he must have been the Chevalier of their mother's twin. This would mean that the blood of Saya and Diva's mother was poisonous to him. However, the explanation of relations never reaches this complexity in the series (they never discuss whether or not both twins share their mothers blood when it comes to killing their mother's chevaliers). By extension, we can assume that Saya and Diva's blood would also both be poisonous to him if this were the case, but he does not crystallize when he comes in contact with Saya's blood, and he reappears at the end of the final episode completely intact.

Saya and Diva's Uncle
The second theory is more popular, firstly because he is clearly homosexual, so is therefore unlikely to father children; and secondly because he is far more interested in Diva than Saya, and speaks of "History repeating itself", leading fans to presume that Saya and Diva's mother was the blue-eyed twin. This also begs the question as to whether or not chevaliers can be "inherited" (as he guarded Diva more than he guarded Saya). In Episode 48, a conversation between Amshel and Nathan further suggests that Nathan is in fact the chevalier of Saya and Diva's mother:

"Nathan: The world exists as a shining stage for Diva so she can be adored. It was proclaimed even before Diva was born.

Amshel: You talk like you've witnessed it.

Nathan: Actually, I did.

Amshel: Hmm?

Nathan: Years ago, there was Saya and Diva and the mummy that was their mother. What she had then was a faithful chevalier just like her daughter today."

It's important to take into account, though, how very quickly he drops the flamboyant façade when confronting Amshel. It's quite possible the flamboyancy is an act, or that the situation for him is a very serious affair.

Manga Version
Nathan makes a brief appearance as a minor character. He shows no connection or memory or hint that he knew their mother. Another contrast is, unlike their anime versions, Diva feels no real attatchment to him and tries to kill him without hesitation when they attack the Red Shield boat. This causes a rift with him and he begins to show disdain for Diva. While Solomon is able to revive him, the damage has been done.

During their last battle, due to Hagi's words, Nathan shows his true feelings. He pushes the sword through Saya and Diva, so that Saya's blood would mingle with Diva's and kill her, making Nathan the one to kill Diva. In rage and anger, Saya unleashes her wrath on Nathan, killing him.