Jerome Guizbatt serves as a Sternritter within the Wandenreich, bearing the Quincy designation "R" for "The Roar" (咆哮 (ザ・ロア), Za Roa). He possesses an exceptionally large, muscular build far exceeding normal human proportions, featuring brown skin and light-colored hair typically styled in cornrows. His appearance includes distinct ape-like characteristics: pronounced upper canine teeth, sharpened fingernails, and patches of dark hair on his forearms and fingers. His attire is a modified Sternritter uniform—a white hooded cloak layered over a trench coat, worn with pants and trench boots. Early depictions varied his hair color and skin tone, initially showing dark hair and a lighter complexion before later appearances solidified dark skin and light hair. Jerome exhibits the characteristic ruthlessness of a Sternritter, showing mercilessness towards enemies. He distinguishes himself through notably low combat restraint, readily deploying his Schrift ability against lower-ranked Shinigami. His involvement is confined to the Thousand-Year Blood War arc, participating in Yhwach's invasion of Soul Society. He gathered with fellow Sternritter at the Gate of the Sun before advancing to the Seireitei, where he helped establish pillars of blue flame during the initial assault. Jerome was part of the trio confronting 11th Division Captain Kenpachi Zaraki early in the invasion. Activating his Schrift, The Roar, proved futile as Kenpachi swiftly bisected him. Kenpachi later carried Jerome's corpse alongside two other fallen Sternritter and presented them to Yhwach. Jerome's spiritual power matches or exceeds that of captain-level Shinigami. As a Quincy, he manipulates ambient reishi, absorbing and combining it with his reiryoku to form weapons; this ability is enhanced in reishi-rich environments like Soul Society or Hueco Mundo. His Schrift, The Roar, triggers a transformation into a more feral, ape-like state, significantly increasing his size. In this form, his powerful roars unleash concentrated sound-based shockwaves capable of mutilating or killing lower-ranked Shinigami at close range. These shockwaves proved ineffective against stronger opponents, only causing temporary deafness to Kenpachi Zaraki. Jerome shares standard Quincy vulnerabilities: his reiatsu is poisonous to Hollows, and Hollow reiatsu is poisonous to him. He utilizes Blut techniques—Blut Vene for defense and Blut Arterie for offense—but cannot activate both simultaneously due to their reliance on separate reishi systems. His character appears solely within the Thousand-Year Blood War arc.