Proof of Humanity

Ningen no Shōmei (人間の証明) is the 3rd chapter of the 2nd volume and the 6th chapter overall of the Before the Fall manga, written by Ryō Suzukaze and illustrated by Satoshi Shiki.

Summary
The civilians of Shiganshina District stand by and cheer as the Survey Corps, led by Carlo Pikale, depart on their first expedition in fifteen years. Inside one of their covered wagons, Kuklo marvels at the everyone's excitement as he scans the crowds for Sharle. As the Corps departs, Sharle watches from the crowds, worrying over whether Kuklo will come back. She notices that some people aren't dispersing with the crowd, and deduces that they must be the families of Corps members.

While hiding in one of the Corps' covered wagons, Kuklo finds a flare gun and begins to fiddle with it as he worries that he may not get to see a Titan before the Corps returns to Shiganshina. As he frets, the wagon runs over a bump in the road, and the resulting jostle causes Kuklo to accidently fire the flare gun. As the Corps' soldiers approach the wagon to inspect it, Kuklo debates whether to fight or flee, eventually deciding to reveal himself and demand to speak with their leader. When he receives no answer, Kuklo decides to try to find the captain on his own, but is quickly detained. With Kuklo restrained, Carlo approaches him and asks his reasons for stowing away on the expedition. Kuklo explains that he wanted to see a Titan and, when asked, denies that he is a member of the Titan Worshipping cult. Carlo explains that he cannot simply comply with Kuklo's wishes, before explaining to him the significance of the flare he just fired, stating that the green flare signals a change in direction when an abnormal situation occurs. Carlo asks Kuklo for his name, but Kuklo is distracted by the sound of footsteps. Kuklo informs Carlo that a Titan is approaching. When asked how he can tell, Kuklo explains that he can hear its footsteps, which surprises Carlo. He asks Kuklo the direction from which the footsteps are coming, and scans the horizon with a pair of binoculars. He is horrified to see that Kuklo is right, and that a Titan is indeed approaching.

As the Titan comes into view on the horizon, Kuklo is horrified at the sight of it, and immediately comes to the conclusion that he is not a Titan. Carlo instructs Kuklo to flee, but Kuklo finds himself frozen in place in fear. As the Corps begins to flee, Kuklo snaps out of his trance and returns to the covered wagon he had been hiding in. Inside the wagon, Kuklo searches for a weapon as the tarp covering the wagon is torn away. Kuklo watches as soldiers attack the Titan's legs, causing it to lose its footing and fall. As dust is kicked up by the Titan's fall, Kuklo notes that they Corps is still far away from Shiganshina and wonders if they will be able to return to Shiganshina. As he turns back to observe where the Titan fell, Kuklo is horrified to see that the Titan has gotten back up and is quickly gaining on the Corps.