Floch Forster began as a member of the 104th Training Corps, training alongside cadets including Eren Yeager and Jean Kirstein. He initially enlisted in the Garrison Regiment but later transferred to the Survey Corps following the Royal Government arc, swayed by heightened propaganda and the regiment's revitalized public standing. During the mission to retake Shiganshina District, Floch received orders to guard the Survey Corps' horses outside Wall Maria. Ambushed by the Beast Titan, he panicked and railed against the prospect of a "meaningless death." Despite his terror, he ultimately joined Commander Erwin Smith's suicide charge against the Beast Titan, galvanized by Erwin's speech urging them to dedicate their hearts to humanity. Miraculously, Floch emerged as the charge's sole survivor, an experience that inflicted severe trauma and profound survivor's guilt. After the battle, Floch discovered the critically wounded Erwin and carried him to Captain Levi, hoping Erwin would receive the Titan serum. He fiercely advocated for Erwin over Armin Arlert, insisting only a "devil" like Erwin could secure humanity's victory. Levi's decision to save Armin instead deeply embittered Floch. He later openly condemned the choice as sentimental and informed Armin that many within the military viewed his survival as an error. Four years later, Floch rose as the de facto leader of the Yeagerists, a radical faction dedicated to Eren Yeager. Convinced Eren was Paradis Island's sole hope for survival, he championed extreme measures, including the Rumbling—a global genocide enacted through the Founding Titan's power. Floch orchestrated a military coup on Paradis, imprisoning or executing opponents and employing scorched-earth tactics against perceived enemies. During the raid on Liberio in Marley, he ignited entire city blocks to deprive adversaries of resources, displaying no regard for civilian casualties. He also exhibited open hostility toward non-Eldians such as the Anti-Marleyan Volunteers and Hizuru engineers, considering them threats to Eldia's burgeoning empire. Floch's personality hardened considerably after the timeskip. He grew ruthlessly pragmatic, prepared to eliminate former allies like Keith Shadis and Levi Ackerman for opposing the Yeagerists. Despite prior camaraderie, he branded resisting former Survey Corps members as traitors. His actions stemmed from a deep-seated fear of external reprisal; he warned that Eren's death would inevitably lead to Paradis's annihilation. In the harbor battle, Floch sustained injuries yet clung to an escaping boat for two days to thwart his enemies from reaching Eren. He fired upon a flying boat vital to their mission, only to be fatally wounded by Mikasa Ackerman. With his dying breath, he implored his opponents not to halt the Rumbling, declaring it the only path to Eldia's survival. Physically, Floch possessed short, tousled blond hair pre-timeskip and stood at a medium height. Post-timeskip, his hair turned auburn with thick bangs swept to the right, and he wore the Survey Corps' updated black uniform equipped with anti-personnel vertical maneuvering gear. His height was estimated at 184 cm (6'03").