The characters you create, as with all great characters, need to have an origin. Some sort of backstory that explains how they've reached the point they're at now. Even though this receives only a limited amount of focus, don't underestimate its importance. It determines their behavior, personality, morals, and how they interact with the world and with themselves. Remember, even though your story focuses on your character living through a set series of (usually linear) events, the foundation for your character, and therefore your story, is established, chronologically, much earlier.

When creating an origin for your character, it is important that it makes logical sense. What I mean is don't make an origin that conflicts with your character's current state of being. Character development should be a well thought out process that develops naturally. Naturally is the key word. If your character is supposed to be an idealistic but rather naïve individual, don't have his origin be witnessing their parents being slaughtered before their eyes. That doesn't logically make much sense. If you're a very clever author though, you might be able to weave this narrative somehow, but there must be steps that bring your character to where they are in a clear, defined, and most importantly natural process.

Knowing this, you might now understand why I choose to think of things in terms of effect then cause, rather than cause and effect. It's because I know what I want my character to be and knowing that makes it easier to work backwards and determine what my character was. If you take for example my character from MHA (referred to as MHA-C, or My Hero Academia Character), you can see how this process was done. I wanted MHA-C to be antisocial. More than antisocial I wanted him to be alone. Someone who has been abandoned by society and those closest to him and has therefore fallen in on himself. Working backwards from that effect, I now must decide the cause. Why is he like this? There are a number of different things that could have led to this point. Perhaps he had a heteromorphic quirk (like Shoji) that altered his physical appearance. Maybe his parents mistreated him and that caused him to learn not to trust others. I decided it was because his quirk made him dangerous. It's up to you as an author to decide.

Another thing that is important to note is the magnitude of cause and effect. Take Newton's third law (didn't think you'd need to refer to physics in order to write, did ya?). Every action has an equal reaction (ignore the opposite part for this example). What this means is that the more drastic of a characteristic you give to your character, the more extreme a personality trait, the bigger the cause has to be. Take for instance the Phineas and Ferb movie: Across the 2nd Dimension. I know, I know, but bear with me. In it, Dr. Doofenshmirtz's doppelganger of the same name, is a tremendously evil villain (in comparison to the original). His reason for being evil? He lost his favorite toy train as a child. Whereas the original, less threatening bordering on only slightly menacing Dr. Doofenshmirtz was abandoned by his family, bullied relentlessly, homeless, on top of a plethora of other things. This is what I mean when I say equal reactions. Now I understand that Phineas and Ferb is a children's show and meant to be very comical, but it still offers this valuable lesson.

Let's again look at MHA-C. If his origin had simply been him being a victim of bullying, he would not be so closed. Distrusting of other people? To some degree, maybe, but not the extreme I've made him. Because of the magnitude of this personality, I needed to create a backstory of equally large proportions. Let's take an in depth look at MHA-C's personality and dissect the reason for each. I will break this down into effect (current state of being) and associated cause (origin). Note that some of these have several layers

Effect: Finds the idea of heroes to be foolish and irresponsible

Cause: Believes that the use of quirks to harm others is morally wrong

Effect: Believes the use of quirks to harm others is morally wrong

Cause: Is unable to use his quirk and is afraid of that fact that he cannot control his power and fears hurting someone

Effect: Is unable to use his quirk and is afraid of that fact that he cannot control his power and fears hurting someone

Cause: The manifestation of his quirk caused the death of his parents

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Effect: Does not trust others

Cause: Believes that everyone will eventually leave him

Effect: Believes that everyone will eventually leave him

Cause: His grandparents abandoned him, and Kendo left him

Effect: His grandparents abandoned him, and Kendo left him

Cause: They were afraid of him

Effect: They were afraid of him

Cause: The manifestation of his quirk caused the death of his parents/the inability to control his quirk unintentionally injured Kendo

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Effect: Finds UA and his classmates intolerable

Cause: Does not understand their desire to become heroes

Effect: Does not understand their desire to become heroes

Cause: Hesitation/inability to use/control his quirk

Effect: Hesitation/inability to use/control his quirk

Cause: Fear of his power and hurting someone

Effect: Fear of his power and hurting someone

Cause: The manifestation of his quirk caused the death of his parents.

These are just a few things working behind the scenes of MHA-C but notice how many layers there are behind each of these characteristics. More importantly, notice how, while each cause-and-effect chain follows its own unique path, they all originate at the same place. This is the crux of the issue. His parents death, which he still blames himself for, has A: Caused him to be abandoned by his grandparents therefore thinking himself undeserving of or incapable of being loved. B: Afraid of his own power. C: Cynical, pessimistic, and untrusting of others. Each of these things was built over time through multiple different facets of his life. The story, and MHA-C's relationship with Yaoyorozu, is based around Yaoyorozu having to fight through all these different facets and disprove what he has learned to be truth. Only by addressing each issue will he finally be able to overcome the many psychological traumas of his past and be able to open himself up to another person again.

Having said all this, let us now turn to my Attack on Titan character (AOT-C). As I mention in the previous chapter, I want my AOT-C to be crazy. The first thing I need to do is determine the nature and magnitude of this trait. How does this psychosis express itself and just how extreme is it? Determining this is up to my discretion as an author and what I think would be the most fun for me to write and for you to read. I still want him to be able to interact with others in a coherent manner. That is, he is still able to live in society (though he may not fit in perfectly) and communicate semi-normally with others.

What causes people to label him 'crazy' is his complete lack of fear when facing Titans. He is not afraid of them, nor is he afraid to die, whether that be being eaten alive or otherwise. He laughs at the prospect of facing Titans, always. He laughs when fighting the Titans, viewing the whole thing somewhat like a game. Where the other character become paralyzed with fear at the sight of others dying, he takes a rather morbid interest and curiosity in it or is very nonchalant towards the whole thing. He speaks in ways that don't always make sense, at least not those around him, but feels no need to explain what he means.

SPOILER AHEAD! SKIP IF YOU WANT IT TO REMAIN A SURPRISE: Spouting things like this to his comrades, "Fear not death, for though your mortal body may perish, your soul will forever thrive, carried by me as I etch your legacy into every fiber of my being!" Though this may sound similar to Captain Levi telling his dying soldier that he will carry his torch, AOT-C will mean it quite literally. When one of his comrades dies, he uses a dagger to carve their names into his flesh, so the scars spell their names. This information will be kept secret from my readers however, and will only be revealed when I find that its revelation has a good use to develop AOT-C. Furthermore, though he is very nonchalant about the deaths of those close to him, it will be revealed that he actually feels for their loss quite deeply and that is what drives him to such measures. It is his way of honoring them.

SPOILER OVER

Now having a good understanding of my character, I work backwards to determine what drove him to this point of insanity. Clearly his mind is fractured (though not completely broken). What events could drive him to this point? I have decided that, like many, he will have witnessed the death of someone(s) close to him during the initial Titan invasion, in this case his parents. But there has to be more, because many people have seen someone be eaten by Titans but haven't lost their minds in the way AOT-C has. So what could I do to further this psychosis? What would you do if you were the author? I decided that not only did AOT-C witness his parents being eaten by Titans, but he was also eaten, more specifically he was swallowed whole. Because he was not dead before being swallowed, nor did he suffer any permanent physical damage, he is completely fine, 100% conscious while in the Titan's belly. While in the belly he sees his parents corpses and must sit with them in a pool of blood for several hours before a scout/garrison member kills the Titan. Once the Titan falls, AOT-C crawls back out of the Titan's throat and survives the assault.

This would be an extremely horrific event, especially for a young teenager, and would lead to some sort of break in his mental state. However, I had another thought when crafting this origin story. If this were to happen to someone, it is likely they would be terrified of Titans. AOT-C would not be laughing in the face of danger, he would be fleeing it at all costs. So there has to be a twist. AOT-C's family life was not a good one. His father was an alcoholic who beat his mother. All AOT-C has ever wanted (during his childhood) is for his family to be happy together. When in the stomach of the Titan, AOT-C believes he will die (obviously). Afraid and alone he clings onto the corpses of his mother and father, and as he surrenders to his fate, he realizes that this is not something he ever had. His parents aren't fighting. Both are holding him, comforting him, and he feels strangely happy and at peace. Due to the trauma of the event, his psychosis somehow warped this into a false positive in his mind. This leads to him associating the Titan's belly, and therefore Titans, with both death and fear, and happiness and peace.

This internal conflict combined with the trauma of said events will damage his psychosis and warp him into the character that I write. It is important to take notice of the equal proportions of the cause and effect, and the additional thought I placed in ensuring the effect made sense in relation to the cause. It follows a defined and natural path of progression.

Now, when it comes to actually placing the origin story into the narrative, you have one of two options. You can either being the story with the origin, such as Attack on Titan did for Eren, Mikasa, and Armin, or you can tell it through flashbacks. I have found that my personal writing style is better suited for telling things through flashback. I feel this allows me to jump right into the story, therefore foregoing the risk of my audience losing interest while I try to build my character. I also find that it adds an element of suspense, as my readers must ask themselves constantly, "what caused this?", "why are they the way they are?", "what happened in their past to lead them to this point?", until I finally decide to reveal it to them.

I particularly enjoy using my origin stories to create a sense of drama and suspense, utilizing it not only as a narration device, but also as a method of getting my readers hooked. They can't help but want to know more, so I dangle hints and clues and occasionally I let them catch small glimpses before quickly snapping the door closed again. This causes a desire to see more, to see the full picture and completely understand how my characters became what they are. And the only way for them to fully understand is by continuing to read.