Liang Ming is one of the few humans in the cast that have no illness or any special powers and can still best an Automaton with one punch if needed. This is because she has been training in martial arts under her father Liang Jian Feng since she was a young girl and thus has known Narumi for a long time and has been trying to find a cure for the Zonapha Syndrome, for both Narumi and her father.

Liang is a fascinating character but suffers because she's not one of the main three, so a lot of her personality and motivations are left in the dark. She is invested in the fight because she wants her father to survive, but whenever she has to fight an Automaton alone, we get glimpses of a bigger story that we just will never get unless prayers are answered and she gets her spinoff anime or manga soon.

First impressions can be very misleading, but in the case of Sadayoshi Saiga, we find out that he’s not just an evil patriarch who doesn’t care for his children, he is even worse than what we imagine when we first meet him and everything we learn about him makes Sadayoshi someone we want dead pretty soon, but at the same time, we want to know more about his past and how he is involved with both the Automatons and their creator, Bai Jin.

It’s easy to draw parallels between them: Both were incredibly controlling and thought that just because they willed their family to love them, they would be loved. Bai Jin, among other things, kidnapped his brother’s wife because he was unable to accept that she loved Bai Yin and not him. Sadayoshi, although he is "Dead" at the time the story begins, has made plans to transfer his mind into his own son's brain to woo a woman too young to be a proper wife. And that’s when the real bombshell lands: Both Sadayoshi and Bai Jin are the same person because Bai Jin has been body-surfing for ages just to stalk the descendants of the woman who dared to love his brother more than she loved him. Let’s be honest, a whole series about his issues would be fascinating to watch, even if it would also be a bit of nightmare fuel.

Another badass character, Liang Jian Feng is Liang Ming-Xia's father and Narumi's martial art teacher. Just like Narumi, he suffers from Zonapha Syndrome, which explains his desire to help find a cure. After all, no one wants to end up locked inside their own body for eternity. But like every other character in Karakuri Circus, Liang has secrets that are revealed little by little to the audience. Just like his daughter, he stays mostly in the background, but whenever he is on the scene, we have to wonder why he is not the main character.

Among the things we know about Liang Jiang Feng is that he’s able to overpower the strongest Automaton despite his condition. That he’s a descendant of one of the creators of the Shirogane and the Aqua Vita and yet chose not to drink it in time to avoid getting sick is probably one of the most interesting things about him. Why would someone who has access to a cure prefer to avoid said cure? Why didn't he tell his daughter and student about the Aqua Vitae? And more importantly, why don't we have a whole series about his past life?

Arlequino is one of the four master Automatons and the musician of the Midnight Circus who is never seen without his lute, not even when he goes into battle. Despite his human appearance, he is a puppet created to make Francine, the leader of the circus, smile at least once. This doesn’t mean that he doesn’t have a personality or free will: in fact, part of what makes him so intriguing is that he’s, at times, more human than some of the human characters.

This is what makes him so interesting: Is he in love with Francine? Or is his unending loyalty just his programming? We know he’s supposed to be quiet and logical, but we have also seen him become angry and act without thinking about the consequences to himself, which should be impossible if Automatons have no emotions. What are his thoughts about them being almost immortal? How does he feel when other Automaton gets destroyed? Arlequino’s existence is so intriguing we can’t help but want to know more about him.

We first meet Guy Christopher in one of the darkest possible places: A hospital for Children suffering from Zonapha Syndrome. As one of the many doctors in the place, Guy seems to be depressed by the knowledge that most, if not all of his patients will suffer a fate much worse than death. Like his coworkers, he drinks and maybe uses drugs to cope with the dark reality of his work, but at times that makes him look as if he couldn’t care less about what happens around him and how the battle develops. This puts him a bit at odds with Eleanor, Masaru, and Narumi, even more so when they find out he's a Shirogane who controls the puppet Olympia and thus the one who can train Masaru to use Harlequin better.

And here’s where Guy goes from “interesting” to “intriguing”. Shirogane doesn't just fight against the Automaton: They're completely immune to Zonapha Syndrome because they were infused with Aqua Vita which makes it impossible for the nano Automaton who cause the illness to attack the human body. This means that Guy has been seeing people suffer while he could, theoretically, save them by forcing a different kind of illness on them. It’s that ethical dilemma what makes him intriguing and another character we wish had more time in the spotlight for himself.

Narumi is our main character, which means we should know pretty much everything about him by the end of the series. However, he’s not as transparent as the usual shonen hero: he has a lot of secrets under his very stoic face. He was raised in China, where he learned martial arts under Liang Jiang Feng and, unfortunately, got infected with the Zonapha Syndrome. He joined a circus to try to make sure people would laugh for him, which brought him back to Japan but unfortunately for him, Narumi is not that funny, which makes it hard for him to stay alive until he meets Masaru, who is willing to laugh for the martial artist.

But what's intriguing about Narumi is that it takes a while for us to figure out what makes him tick. Because while he’s quite honorable, a good fighter, and a loyal friend, it’s weird that he doesn't seem to care about other Zonapha Syndrome’s sufferers until after he sees the late-stage patients in the hospital; it’s also weird that before helping Masaru, he tried to pretend he didn’t care about strangers in general. What made him become that way when he had always had the help of others to survive? That's just one of the many questions that make Narumi far more intriguing than other shounen main characters.

At first sight, Masaru Saiga had a perfect life. He was the heir of the Saiga empire, and his mother loved him dearly, which meant that he had practically everything a young child could want. But after his father died, things got really bad for him. Sure, he inherited a vast fortune and the puppet Harlequin that could protect him, but in exchange, it seems that every single member of the Saiga clan wants to kill him or worse.

And yet, he still can’t hate anyone. When he finds out that his father is not only trying to hijack his body but also force Eleanor to marry him, Masaru realizes Sadayoshi is evil and, even then, he stills feel sorry for the man. When Narumi almost let him get captured by the puppets, Masaru still forgave him and later became one of his biggest supporters. By the end, it’s hard to understand how Masaru is such a nice person despite all that he has suffered and that is what makes him so intriguing.

When we first meet Eleanor, we don't get to learn her name. That alone makes her immediately intriguing because in a world where living puppets don't take a lot of precautions to hide their existence, why would a human avoid using her name? She seems very stoic and withdrawn from society and since she's devoted to protecting Masaru with her life, at the time, it would be easy to think that Eleanor is not a human but an Automaton. Finding out that she's 91 years old and still looks not a day over 25 doesn't make it easier to believe she's human.

Among the main characters, Eleanor is the most mysterious. We know she was raised in France, where she was also taught the art of puppetry from the moment she was able to walk. While she was treated like royalty, she was also taught to ignore her feelings and that in the end, she was nothing more than another puppet. And as we're trying to figure out what it means, we get another bombshell: She's a Saiga by birth, which makes her Masaru’s aunt. And that’s not even the last secret that this woman has for us.

Francine is one of the most mysterious characters in the whole story starting with the fact that we never know exactly who is the “real” Francine. The first one we meet is the leader of the Midnight Circus, who is considered to be the cause of the Zonapha Virus. As all the Automata in the Circus are dedicated to trying to make her smile, every action they take can be considered her fault. Then we find out that this Doll Francine is a fake, that there was a real Doll Francine before her who created her body double so she could quit being Queen Automata and try to find her way to smile in order to be able to please her master.

That’s where the story becomes really complicated. We have two mysteries to be solved: Francine’s “master”’s identity—the real big bad of the tragedy if we’re to be honest—and the reasoning behind Francine’s creation, which, as you can imagine, is connected to the Zonapha Virus, to Ban Jin and his desire for immortality, and to every single bad thing that has happened to all the characters in the story. The final reveal which coincides with the appearance of a third Francine who happens to be human makes Francine the doll the backbone of the story’s mystery.

Now, if Francine—all of them—are behind the mystery of the whole series, who could be more intriguing? Well, that’d be Angelina, one of the very first Shirogane created to fight the Automata. Because, while Francine is the cause of everything that happens, Angelina is the key to solving the riddle that is the whole series, and she manages to do so despite being behind the scenes and dead from the beginning of the story. We first learn that she was the daughter of Lucille Bernouille, the very first Shirogane and that she held the Soft Stone within her body to make possible the creation of more Aqua Vita. But that is her only connection to the main cast.

The problem with Angelina is that she is a walking spoiler. Practically any answer about her past will give you a hint of the ending of Karakuri Circus. Which, of course, makes everyone want to know more about her. We know that she met Guy when he was younger and she was pregnant, so we know that Shirogane can get pregnant but, what happened to the child? We also know that she is no longer alive, and that begs the question, who could have killed her? And more importantly, what happened to the Soft Stone?