Yokumiru Mera is a middle-aged man employed by the Hero Public Safety Commission. He possesses a lanky build, stands approximately 171 centimeters tall, and has beige, chin-length messy hair. His black eyes are often underscored by noticeable eye bags stemming from chronic sleep deprivation. His typical attire consists of a formal black shirt over a white undershirt, black pants, a loose tie, black shoes, and a microphone for announcements. Characterized by persistent exhaustion from overwork, he frequently complains about fatigue and maintains an unenthusiastic, blasé attitude towards his duties. Despite this weariness, he occasionally demonstrates inspirational qualities, particularly when addressing aspiring heroes about responsibility and the challenges of hero society, maintaining a pragmatic approach to his responsibilities while expressing a desire for rest. He first appears as the chief supervisor of the Provisional Hero License Exam at Takoba National Stadium, overseeing the initial phase involving 1,540 examinees. He explains the rules, announces results, displays shock when examinee Inasa Yoarashi eliminates 120 competitors instantly, commends successful candidates, and offers remedial courses to those who fail. He later oversees this remedial course alongside Gang Orca, introducing participants and facilitating the practical test involving primary school children. His role includes making administrative decisions, such as permitting Camie Utsushimi to retake the exam after her identity was stolen. Following increased villain activity, he represents the Commission in initiating the Hero Work Recommendation Project, meeting with U.A. High School principal Nezu and All Might to communicate the program. During the Paranormal Liberation War, Yokumiru participates in a Commission operation to apprehend Rikiya Yotsubashi. The operation fails when Yotsubashi's double attacks the headquarters, resulting in numerous casualties, including the death of the Commission president. Yokumiru survives injured and is seen holding the president's body. After this attack, he assumes the role of acting president of the Hero Public Safety Commission. In this capacity, he authorizes strategic decisions during the final conflict against All For One, including approving the involvement of unlicensed individuals like Hitoshi Shinso in operations. Following the war, he is succeeded by Hawks as the new Commission president. His quirk remains officially unidentified across all media.