There are some villains in anime that absolutely no one saw coming and are thus well-executed twist villains. However, other twist villains were too obvious or predictable from the beginning and disappointed viewers upon an unsurprising reveal.
Some characters were obvious twist villains thanks to fake-out deaths, acting as side characters that characters knew little about before their final reveal, and how they acted nice in front of peers compared to how they truly were in reality. From Sirius Dieke to Leon Von Schroeder, these so-called twist villains mainly disappointed fans with the buildup (or lack thereof, in some cases) to their reveals.
10 Sirius Dieke Was A Side Character That Viewers Knew Little About Before His Reveal (My Next Life As A Villainess: All Routes Lead To Doom!)
Sirius Dieke from the romance anime My Next Life As A Villainess was faking his identity the entire time, and his real name was Raphael Walt. He was the illegitimate twin brother of the real Sirius Dieke, who was dying from illness. Sirius' mother tried to make Raphael's body the new vessel for Sirius' personality using dark magic.
However, it only gave Raphael Sirius' memories and nothing else. Raphael was forced to impersonate Sirius and somehow acquired dark magic until a good time came for him to get revenge. Unfortunately for fans, they saw the twist of Raphael pulling the strings too easily since they knew little about him before his reveal as the villain of the series.
9 Fino Bloodstone's Position Alone Hinted At Her Becoming A Twist Villain (I Couldn't Become A Hero, So I Reluctantly Decided To Get A Job)
Fino Bloodstone was the daughter of the Demon King. However, after the Demon King was defeated, she was forced to find work instead of taking up her reign ruling all of the demons instead. Her position alone made many fans note that she could potentially become a twist villain immediately, and they were proven right in the series' last few episodes. Thankfully, the protagonist, Raul Chaser, stopped her before she started seriously taking up her reign as the new Demon King by making her come to her senses as her normal self.
8 Kirihiko Karasuma Showed Up Out Of Nowhere (Kamichama Karin)
Kirihiko Karasuma was Kirio Karasuma's father and ultimately the final villain that Karin and her friends faced. Unfortunately for viewers, the buildup to Kirihiko even showing up was fairly sudden and felt thrown in at the last second to make for a great finale.
His appearance out of nowhere both shocked and disappointed fans. Not only did Kirio not get to shine as a villain thanks to Kirihiko hijacking his body in the finale, but Kirihiko's villainous reign was short-lived since he was defeated as soon as he arrived.
7 Mami Antagonized Shizuru And Kazuya Instead Of Giving Them Space (Rent-A-Girlfriend)
After Mami broke up with Kazuya, she was shocked to find out that he had a new girlfriend named Chizuru (though, in reality, Kazuya rented Chizuru). Instead of giving Kazuya the privacy he wanted with Chizuru, Mami went out of her way to lead on Kazuya, antagonize Chizuru, and ultimately cause a rift in the friendships she had with Kazuya and their other peers. Many fans were not surprised that Mami took up an antagonistic role considering how she broke up with Kazuya in the first place, and her actions made her into a badly-executed twist villain.
6 Madame Red Being One Half Of Jack The Ripper Did Not Surprise Some Fans (Black Butler)
Madame Red and Grell Sutcliff were both revealed to be working together as Jack the Ripper. After the arc's initial suspect was revealed to be incorrect, many fans figured that Red had to be responsible, even if they did not know exactly how she did it. After it came to light that Grell was assisting her, however, fans immediately knew that Madame Red had bloody hands in the murders, though she did not kill them herself. She had a whole list of all the prostitutes that had abortions, and Grell killed them in the same order they went under the knife.
5 Trip And Virus Were Suspected As Twist Villains From The Beginning (DRAMAtical Murder)
Considering how little the viewers knew about Trip and Virus, despite their friendship with Aoba, these two characters were immediately suspected of being twist villains. This turned out to be correct when Trip and Virus revealed themselves to be working with the main villain, Toue, and that both men were deeply obsessed with Aoba to the point of keeping him as their plaything.
Thankfully for some viewers, the latter point was mainly portrayed in the OVA, which compiled all of DRAMAtical Murder's bad endings.
4 Gaku Yashiro Being The Murderer Surprised No One (Erased)
Gaku Yashiro was initially presented as a red herring in Erased when the cast tried figuring out who the murderer was. Some fans hoped that Gaku was just a red herring and nothing else, considering how evil he came off with his looks and overall personality as is. However, it was later revealed that it was Gaku that was the true murderer and main villain all along. None of the viewers were surprised at all by this outcome and felt that this so-called twist villain was way too obvious to be entertaining at all.
3 Leon Von Schroeder Was Zigfried's Little Brother (Yu-Gi-Oh!)
Zigfried Von Schroeder was an obvious villain when he was introduced during the KC Grand Championship arc. Many viewers were not surprised when it was revealed that Leon Wilson was Leon Von Schroeder, Zigfried's little brother. Both brothers looked fairly alike with their pink hair and the overall aesthetics of their decks, so none of the viewers were surprised by this twist.
Additionally, Leon did not fully want to go along with Zigfried's plans to begin with, and even tried to get rid of the "Golden Castle of Stromberg" card himself the moment he played it and found out about it spreading a virus in Kaiba's computers.
2 Isabella Putting On A Warm Front Was Obvious To Some Fans (The Promised Neverland)
Some fans were not surprised that Isabella was in on raising children in the orphanage to be meat for the demons. This reveal was later made more obvious when Isabella herself showed little-to-no regrets over her actions, including breaking Emma's leg to prevent her from escaping. However, Ray, Emma, and several other orphans managed to escape the Grace Field House despite Isabella's best efforts to keep them there, much to the relief of some fans. There was a better twist than Isabella being a villain, however, and that was Ray both being her son and acting as a spy for her.
1 Sōsuke Aizen's Sudden Fake Death Made The Twist Obvious To Fans (Bleach)
Sōsuke Aizen was initially loyal to the Soul Society as one of its members. However, his sudden death made fans wonder if it was real and was a set-up for him becoming a twist villain. Their suspicions were correct when Aizen reappeared later on and revealed that he wanted to destroy the Soul Society and had to fake his death to get away from them. Viewers were split on whether this twist was good, and some who liked Aizen were mad about him becoming a twist villain because of the bad fake-out death and lack of lead-up to the reveal.