The Boy Inside the Walls

The Boy Inside the Walls (壁の中の少年) is the 4th and final chapter of the 23rd volume and the 94th chapter overall of the Attack on Titan manga, written and illustrated by Hajime Isayama.

Summary
Arriving on the outskirts of Liberio, an ecstatic Gabi celebrates returning home while an uneasy Falco observes Reiner. Falco recalls that Reiner's failures on Paradis were overlooked because of his unquestionable loyalty to Marley, Falco is perplexed by Reiner's plea to "save" Gabi from inheriting the Armored Titan, and begins to question whether he can be trusted.

Inside Liberio, the returning Eldians are greeted by their families. As Reiner and Gabi are greeted by their family, Falco is distracted by the sight of a large number of wounded Eldians who are being escorted away. Koslow explains to Falco that they were left traumatized by the war, and are being taken to a nearby hospital for treatment, as they have no families to return to. As the official happily begins tormenting the soldier, Falco asks his family to return home without him, and attempts to help one of the injured soldiers.

Later, Reiner and his family have dinner with Gabi's family at their house. Gabi recounts how she single-handedly destroyed the Armored Train at Fort Slava, and Reiner's mother, impressed, asks Reiner if she will become a warrior. Reiner assures her that, based on Gabi's record, she will likely become the next warrior. Karina is delighted to hear that a second member of their family will become a warrior, noting that all that is keeping them from being happy is the inhabitants of Paradis. This prompts a number of questions for Reiner from his family about the people of Paradis. Although Gabi insists that Reiner should not be forced to answer any such questions, Reiner agrees to tell them about his time in the military on Paradis.

Reiner informs his family about the hardships he endured while among the evil Eldians on Paradis. He begins by recounting his experience with one Eldian who had stolen a potato, and attempted to bribe her instructor when she was caught. He describes the people he met as idiots, hypocrites, and serious people. Reiner makes special mention of an Eldian who had been obsessed with revenge, and the people who followed him no matter what he did, and concludes by saying that it had been a nightmare for him, Bertolt, and Annie to be stuck with such a diverse group of people.

Gabi is puzzled by Reiner's choice to describe the people of Paradis as "diverse" but his mother is quick to remind her that all of the inhabitants of Paradis are evil. She tells Gabi that the people of Paradis could choose to leave the island at any time and destroy the world with their Titans, and that they, the good Eldians of Marley, are the only ones with the power to stop such a thing from happening.

Later, Reiner lies in his old room and recalls his childhood. Reiner never knew his father, a Marleyan man, as relations between Eldians and Marleyans were strictly forbidden. As a result, he chose to join the warrior program in the hopes of becoming one of the Nine Titans so that he and his mother would become honorary Marleyans and would finally be able to reunite with his father. Despite performing unexceptionally in the program, Reiner was among the seven children chosen to be a warrior Cadet.

One day, Zeke, another cadet, announced to the cadets that an attack on Paradis was being planned, and that the time for the next warriors to be chosen was drawing near. Reiner was ecstatic to hear that he would soon become a Marleyan. Galliard, annoyed at Reiner's optimism, reminded him that the only positive trait he had demonstrated as a cadet was his intense loyalty, which would not be enough to gain one of the seven Titans in Marley's possession. Reiner, believing Galliard to be making light of the warriors' mission, threatens to report him for treason, resulting in Galliard angrily striking him. As Marcel separates the two, Galliard proceeds to mock Reiner before leaving with Zeke. Bertolt helps Reiner up as Reiner despairs at the thought of not being chosen for one of the Titans. Bertolt reassures him that there is still a chance for him to be chosen, based on his loyalty.

As the two go to catch up with their fellow cadets, Bertolt asks Reiner if he is okay with becoming a Marleyan if it means he only gets to live thirteen more years. Reiner responds that, in thirteen years, he will be a hero for having defeated the devils living on Paradis.

Elsewhere on Paradis, a young Eren Yeager watches the sky and hopes that something interesting will happen to him.