WARNING : the next post contains spoilers for people who have not read the manga to chapter 109.
For those of us who have read the manga to the last issue published in September 2018, one thing is clear: for Hajime Isayama, creator of Shingeki no Kyojin, good or evil depends on perspective. The author brings us the drama of war and makes readers crash into the harsh reality... being a villain or hero only depends on who is telling the story.
The story of Shingeki no Kyojin begins from the eyes of Eren, Armin and Mikasa. Three children who live inside the walls curious to see the outside world, until the day the titans arrived. In the first episode we experienced all the terror that flooded the protagonists, especially Eren when he saw his mother being devoured alive by a titan. Since then, the goal of our main character was clear: revenge and the absolute destruction of the titans to save humanity.
Eren's hatred would be his driving force in a world where survival is part of the routine. Our protagonist doesn't understand why he must live inside walls to avoid being devoured by creatures whose existence he doesn't comprehend. As if that weren't enough, Eren discovers that he possesses a power that allows him to become a titan at will (activating it when he hurts himself) and progressively begins to see this ability as an instrument to eliminate the titans.
Eren's perspective begins to broaden when, through physical contact with Rod and Historia Reiss, he recovers some memories of his father and discovers that it was he who transmitted the titan powers to him. For some reason Eren was unaware of, his father Grisha Jaeger murdered almost all the members of the Reiss family transformed into titan, and stole the Founding Titan's powers from Frieda Reiss. After the fall of the Maria wall, Grisha injected Eren with a serum that turned him into a titan, and he devoured his father, thus inheriting both powers.
In the Return to Shiganshina arc, Eren finally uses the key his father left him to find a diary in the rubble of what was once his home. In this diary, Eren discovered the truth: there is a country called Mare, far from the island of Paradis, where Erdians (descendants of Ymir, those with titan blood in their veins) are treated like second-class citizens and live locked behind walls and with banners in their arms that identify them as such (a very clear allusion to the treatment of Jews during World War II).
Why? For a "sin" that occurred hundreds of years ago. Erdia was a powerful empire that arose with Ymir Fritz, the first mortal to gain titan power, and upon her death that power was divided by 9. The Erdians dominated the rest of the world (mainly the nation of Mare) with titan power for many years, until the 145th king of Erdia, Karl Fritz, was ashamed of the actions of his empire and joined one of Mare's families, the Tybur, to create the story of a false hero who "defeated" King Fritz and forced him to flee to the island of Paradis.
This gave way to the civil war between the Erdians and, finally, Mare seized 7 of the 9 titan powers and took prisoner the Erdians who could not escape with King Fritz. This is how they ended up being considered "demons" by the people of Mare.
Grisha discovered at a very early age the cruelty of Mare's soldiers and how the life of the Erdians meant nothing to them, with the murder of his little sister, so he joined the resistance of Erdia and married Dina Fritz, a descendant of royalty. However, years later, their first-born son Zeke Jaeger would betray them with Mare's soldiers (for which he would since become known as "Boy Wonder"), and they would suffer the punishment imposed on all the rebels of Erdia.
They were taken to the island of Paradis and injected with serum to turn them into titans, condemning them to wander eternally and devour their brothers. Just before being injected, Grisha was saved by Eren Kruger, an Erdian infiltrated into Mare's ranks. He possessed the power of the Attacking Titan and entrusted Grisha to continue his mission: to obtain the power of the Founding Titan, which lies within the walls of Paradis, and to liberate the people of Erdia.
At this point, both Eren and the readers think that the enemy has been revealed. It's not the titans; it's the people of Mare, those who live beyond the sea. They are the ones who have turned Erdians into titans and forced them to wander and eat their own people. It is they who are to blame that the Erdians of Paradis live in fear, imprisoned within walls.
And it is at this point in the narrative that Isayama decides to change our perspective, telling us the story of Reiner, Bertholdt and Annie. Erdian children who grew up in Mare, within walls (different from Paradis, but still walls) under a doctrine: in the veins of the Erdians runs the blood of the devil. The Erdians are not like the citizens of Mare because they must bear the sins of their ancestors, in them is evil and it is their duty to exterminate that evil, that is to say, to kill the demons of the island Paradis in order to save humanity.
The "warriors" are children indoctrinated with this line of thought, to inherit the titan powers that Mare possesses and fight for a nation that treats them like scum.
Reiner, Bertholdt, Annie and Marcel were sent to Paradis, considered by their families as "heroes," to fulfill a mission, recover the powers of the Founding Titan and destroy Paradis. Eliminate the demons.
Shortly after their arrival in Paradis, the children were attacked by a titan and Marcel sacrificed his life to allow Reiner to flee with the others. Despite the fear and the loss of a friend, they would continue their mission. The demons of Paradis island definitely deserved destruction.
The demons...
It was not a demon that Bertholdt's eyes saw, turned into the Colossal Titan, when he destroyed the Maria wall. What he saw were terrified children, Eren, Armin and Mikasa, whose lives would be destroyed in seconds.
It is at this point that the two stories intersect, and Mare's warriors begin to realize that the "demons" they were told about in their country were not such. By infiltrating Paradis' soldiers, they formed friendships and were able to see their point of view. This caused the hearts of these characters to split, understanding that the mission they carried out involved killing innocent people who did not deserve it. Especially in Reiner this wreaked havoc, and his mind formed two personalities, that of Mare's warrior, and that of the soldier who survived between the walls of Paradis with his companions and took care of them.
Who is the hero here? Who is the villain? Years later, infiltrated into Mare, Eren would understand this perfectly by living with his enemies. Eren confronts Reiner and, contrary to his impulsive character, calmly explains to him that he understands everything he has felt. That they were naive children who were brainwashed and convinced to kill the "demons" that inhabited Paradis island, who did what they did, convinced that it was the right thing to do. Reiner listens incredulously to an Eren that he hadn't seen for 4 years, when the last time they saw each other they fought to the death, and the only thing Eren wanted to do at that time was to kill him for being a traitor and for being a "monster."
"I'm the same as you. I didn't have any other choice," Eren tells him.
It's Eren's turn to be the executioner. He has decided to attack Mare by surprise, sacrificing hundreds of innocent lives, this time before the eyes of other children, Gabi and Falco, who watched in horror as their lives were destroyed in seconds, and their friends were killed for no reason. Eren Jaeger declared war on the world.
On this occasion, Eren and the Survey Corps are the wicked, the enemies who come to destroy everything without mercy. This leaves the spectators with a choice:
Which massacre will we support? Who are the good ones? Who are the bad ones? We will discover that these questions are not so easy to answer, and we only know one truth: both sides have victims and perpetrators.
The words of a member of the Military Police to Hange Zoë resonate: "This is an endless cycle. When the executioner's role ends, another takes his place, and so on. Courage, Hange."