Senior Pilot Vulgar Hummer serves aboard the Subaru spacecraft, holding the military rank of First Lieutenant (Chuui). He stands 1.85 meters tall, weighs 87 kilograms, and sports dark blonde hair, petrol-colored eyes, and distinctive scars. An American national born on August 10 with blood type O, Hummer possesses a rough, masculine exterior masking genuine concern for his mentee, Subaru Ichinose. His protective nature and passionate approach, however, often unsettle or annoy Subaru, creating a dynamic of overbearing guardianship.

Hummer appears throughout both seasons of the animated adaptation as a pilot engaged in the spacecraft's conflicts. His character extends to other media, including a stage play adaptation where actor Yūsuke Ueda portrayed him. Large-scale stand figures based on his likeness feature among the series' merchandise offerings.