TV-Series
Description
Kōta Tsuchiya, nicknamed "Muttsuriini" ("Voyeur" in English), is a reserved and antisocial student in Class F at Fumizuki Academy. Despite his quiet nature and perpetually morose expression, he holds the infamous reputation as the school's ultimate pervert, dubbed "The Silent Ninja Pervert." He rarely speaks but remains a core member of Class F's inner circle alongside Akihisa Yoshii, Yūji Sakamoto, Mizuki Himeji, Minami Shimada, and Hideyoshi Kinoshita.

Academically weak in most subjects, Kōta excels exceptionally in Health and Physical Education, his scores surpassing even the teacher's. This expertise manifests in his summon beast, which wears a ninja outfit and wields kodachi swords. This beast evolves situationally: adopting a modified hakama and developing an obsessive attraction to Yūji Sakamoto's summon during a field error; transforming into a vampire during a test of courage; and appearing as an adult photographer in a future-teller scenario—an outcome disappointing to Kōta, who aspired to be a pornography creator. The summon beast carries a large camera, reflecting Kōta's own skills in photography and surveillance.

Kōta's perverse tendencies drive him to covertly take illicit photographs, especially panty shots, and meticulously document female students' bust sizes. Paradoxically, he suffers extreme reactions to sexual situations, enduring massive, sometimes unconsciousness-inducing nosebleeds when confronted with suggestive imagery or his own thoughts. Aiko Kudō's teasing provokes particularly strong reactions, hinting at potential romantic interest. He also exhibits heightened responses to Hideyoshi Kinoshita's androgynous appearance, once preparing blood transfusion packets anticipating fatal nosebleeds upon seeing Hideyoshi in swimwear. Despite his voyeurism, his classmates generally tolerate his behavior.

Possessing masterful stealth and information-gathering abilities, Kōta operates a lucrative business selling photographs, including Hideyoshi compilations and action shots of Minami Shimada assaulting classmates. He trades these photos for favors, such as offering Akihisa a free picture of Minami in exchange for purchasing one of Hideyoshi. He has two older brothers and a younger sister, later implied to have died after consuming an imitation of Himeji's toxic cooking.

Beyond transactions, Kōta shares a long-standing friendship with Akihisa dating back to first grade. He actively participates in group activities like beach trips and training camps, where his perverse pursuits often drive plot points—orchestrating spy missions to identify blackmailers or inciting avatar battles to protect illicit activities.