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Sylvia (In Japanese: シルビア, Shirubia) was a major antagonist in the light novel, manga and anime series KonoSuba: God's Blessing on this Wonderful World!. She served as the main antagonist of the fifth volume of the light novel, the ninth volume of the manga, and the 2019 anime movie KonoSuba: God's Blessing on this Wonderful World! Legend of Crimson. She also had a cameo appearance in the spin-off light novel and manga Consulting With This Masked Devil!.
Sylvia was a creature known as a chimera, an organism capable of artificially manipulating the structure of her own body. As such, Sylvia possessed both male and female anatomy. She served as one of the eight generals of the Demon King's army, acting as the director of the Monster Enhancement Bureau.
Perhaps due to her incredible magical resilience, Sylvia was sent by the Demon King to annihilate the Crimson Demon Village and secure the Mage Killer weapon. The Crimson Demon Clan were a race of incredibly powerful mages who all possessed dramatic tendencies. Unfortunately, due to the strength of the Clan, Sylvia's armies were easily decimated and she struggled to make any progress.
In Legend of Crimson, Sylvia was voiced by Akeno Watanabe. Watanabe has also voiced Tayuya in Naruto, Villetta Nu in Code Geass: Lelouch of the Rebellion, Kycilia Zabi in Mobile Suit Gundam: The Origin, Sherry Cromwell in A Certain Magical Index, Anna Williams in Tekken: Blood Vengeance, and Dr. Octopus in the Japanese dub of Spider-Man: Into the Spider-Verse.
Sylvia had free-flowing bangs that were highlighted red and long, straight hair partially kept up in a bun. Her eyes were purple and she had pointed ears similar to an elf (except in the movie), leading Kazuma to believe she might be some kind of demon.
At first glance, Sylvia appeared as a towering, voluptuous, and beautiful woman. She was so attractive that Kazuma seriously considered defecting to the Demon King's Army to be with her, although this was before he realized that Sylvia had male genitalia.
As a chimera, Sylvia possessed traits typically unique to both males and females. She had the breasts and figure of a woman and male features which couldn't be picked up on as easily, such as a penis.
She wore a crimson leather one-piece dress made from the skin of low-level devils, white-sleeved gloves, brown stockings, dark-red shoes, a gold necklace, and a single blue earring on her right ear which isn't present in the movie. She usually carried a rope around with her to use for the "Bind" skill (except in the movie).
After fusing with the "Mage Killer" weapon, Sylvia's lower body was replaced by a giant white snake-like tail. Her clothes were completely shredded with the exception of her necklace and some red cloth that hanged atop her breasts.
In the movie, upon escaping death and fusing with Beldia and Hans, Sylvia's appearance altered drastically. Like with the Mage Killer fusion, only her her upper body remained. Her hair changed into a blue-luminescent slime and her clothes were completely gone, only being covered by orange wedge-like patterns on her breasts. Her size increased drastically, to the point where she completely dwarfed the likes of Kazuma and Wiz. Sylvia's lower torso was made up of blue luminescent slime covered in armor platting in the shape of a four-legged animal.
Sylvia was a smart and charismatic leader who seemed to genuinely care about the well-being of her subordinates, often shielding them from the magic of the Crimson Demons. She could be very observant, such as when she deduced that Kazuma wasn't the famed magic swordsman Mitsurugi by noticing the low quality of his blade.
Shes quite the seductive type as well, mainly due to the fact that she wanted to seduce Kazuma when he was taken hostage.
Sylvia also likes to taunt her enemies and make rude remarks about their strategies and their predicaments. When shes angry, Sylvia's voice all of a sudden deepens and sounds more masculine.
Upon her near death experience Sylvia realized that she had never been truly happy, but merely satisfied with her life. Sylvia sought true companionship, someone who would love her that they could love back. She chose to live for love and hope and the bright future that she could strive towards. Sylvia's newfound feelings were so strong that they were able to hold back the entire might of the Crimson Demon Clan.
In the movie adaption Sylvia's feelings for Kazuma went beyond mere physical attraction, as she had fallen in love with him by the end of the film. Sylvia's attraction to Kazuma was so strong that his betrayal lead to her strong resolve being completely shattered. Despite Kazuma's betrayal, in her last moments, Sylvia declared that she still loved him.
She was shown to be an extremely benevolent leader, often showering her incompetent army with praises where others would punish them.
Sylvia was a chimera, a creature which could assimilate living creatures and magical items into its physiology to grow stronger, as such a lot of her physiology was artificial. Eventually, she joined the army of the Demon King as one of the eight generals who maintain the barrier around his castle, and became renowned for having the greatest magical resistance out of the Generals.
At one point a powerful Lich by the name of Wiz laid siege to the Demon King's Castle. Sylvia was one of the Demon King's generals who went to confront the Lich, however she proved too powerful for Sylvia, who was defeated. The Demon King was fortunately able to convince Wiz to join his army as one of his eight generals.
Perhaps because of her magical resilience, Sylvia was sent with an army to annihilate the Crimson Demon Clan, a race of genetically modified humans who were highly proficient at magic and had been a constant thorn in the Demon King's side.
Sylvia and her forces were no match for the Crimson Demons, as, although Sylvia had great magical resilience, her troops did not. Furthermore, although Sylvia was very resilient, she didn't have enough offensive power to deal with the Clan. Eventually Sylvia's objective shifted to obtaining and merging with a weapon sealed within the Village known as the "Mage Killer".