TV-Series
Description
Utsugi Tsukimiya attends Mitoya High School and belongs to the circle around Seri Koyuki and Kabuto Hanadori. He possesses medium-length ochre-brown hair and typically keeps his eyes closed. When his eyes open, they reveal heterochromia: the left eye red, the right green. His standard outfit combines a collared shirt over a black undershirt.

Outwardly cheerful and sociable, Utsugi presents a friendly, approachable face to classmates. This amiable facade conceals a manipulative and sadistic nature; he finds amusement in others' embarrassment or misfortune, often covertly capturing these moments in photos or videos for later enjoyment. His sharp ability to deduce people's thoughts allows him to manipulate situations effortlessly, bullying others while maintaining his pleasant exterior. Despite this tendency, he occasionally shows genuine concern for friends, leveraging his manipulative skills to assist them. Academically gifted, Utsugi consistently scores 100% on exams without visible effort, creating illustrated study aids that link scientific concepts to anime characters. He also demonstrates skill in drawing manga.

Utsugi initiated Kabuto Hanadori's introduction to Seri Koyuki, setting their early interactions in motion. He later assumes care for Cerberus, a puppy Kabuto found, after offering since pets were prohibited at Kabuto's residence. Utsugi also owns a pet cat at home. He participates in the club formed by Seri, Kabuto, and their homeroom teacher. In discussions with Seri, particularly about Seri's desire for a "normal life," Utsugi suggests that wanting normality implies its absence, questioning Seri's self-perception. His astrological sign is Sagittarius.

He frequently interacts with Seri and Kabuto informally, coordinating meetups at shopping malls and messaging Seri about progressively closer locations to Seri's residence. He joins Seri playing video games on the school rooftop, expressing enjoyment for simulation games involving domestic management. His interactions sometimes involve preventing Seri from avoiding Kabuto, urging Seri towards forgiveness. During exam preparations, he shares his unconventional study materials with Seri and later comments on the dangers of underestimating others when test results reaffirm his academic performance.