Vooren Grantz is a mage soldier from the Empire's military in "The Saga of Tanya the Evil," serving in the 203rd Aerial Mage Battalion under Tanya von Degurechaff. He participates in combat within an alternate World War I-like conflict as a dedicated Imperial soldier. In the crossover "Isekai Quartet," Grantz appears as a student, interacting with characters from various isekai series. He is part of the "Intercom Committee" with Megumin. His design features blonde neck-length hair and green eyes, consistent across depictions. Grantz is consistently shown alongside his 203rd Battalion comrades Matheus Johann Weiss, Wilibald Koenig, and Rhiner Neumann. This group dynamic persists in both combat and school settings, emphasizing their collective role as Tanya's subordinates. In "Isekai Quartet: The Movie – Another World," Grantz fights swarms of small golems alongside Tanya, Visha, Weiss, and Raphtalia. Informal fan observations describe Grantz as earnest and occasionally naive. Some interpretations suggest he might perceive Tanya as a maternal figure due to his loyalty and admiration for her leadership, aligning with his portrayal as a younger soldier reliant on her command. His character lacks significant documented development or expanded backstory beyond these established roles.