[🐹] • Gundham Tanaka

One detail he revealed about his past was that he lived with his mother during his childhood. Although they seemed to have a good mother-son relationship, his culinary skills left much to be desired. With no choice but to silently endure her terrible cooking so as not to make her cry, Gundham began to believe his body was "poisonous" and carried "a terrible curse." He then used his home life to create a defensive persona and prevent other people from touching him, claiming they would "immediately decompose and wither away." He applied this in elementary school, where it was revealed that he never shook hands with other children. He would pretend to be sick and stand near the teacher to avoid questions. He also frequently skipped folk dances at school, managing to skip participating thanks to a nurse who sympathized with him, or as he put it, "of the same tribe." He also mentioned that he had only been to an amusement park once during his childhood and that no one had ever bought him a toy. Gundham seemed to have an absent father, as he never mentioned him except in a few hints. He once described himself as "the son of an angel and a demon" and "the result of the union between a human and a demon." Considering his mother was the only parental figure he mentioned who made an effort to raise him, it could be inferred that the "angel/human" part referred to her, while the "demon/devil" part likely referred to his absent father.

While attending Fazal Commercial High School, Gundham became a prominent member of the Breeding Club thanks to his ability to domesticate any animal and his success in breeding endangered species. A joking rumor circulated that he could also talk to animals. However, his most notable contribution was his operation of a website related to animal breeding. The true contents were never revealed, but he claimed that the results of his research were eagerly awaited by scientists (or "witches") around the world. The website was said to be highly secure (or "magically enchanted"), so only selected individuals could access it, while ordinary people could only access the fictional site called the "Exciting Breeding Diary." Gundham also conducted his own research on ethical breeding, and his latest project was a hybrid hamster with "glistening silver fur" featuring dominant spots and bands. In addition to this and many other animals he cared for at home, he entrusted their care to people he selected to help him with his breeding duties.

Gundham always carried the Four Dark Devas of Destruction (破壊神暗黒四天王, hakai-shin ankoku shiten-ō, lit. Four Heavenly Kings of Darkness and Gods of Destruction), his four hamsters, on his scarf. Their names are Supernova Silver Fox San-D (orange and white), Mirage Golden Falcon Jum-P (the ever-sleepy tan-furred one with a peach-colored belly), Crimson Steel Elephant Maga-Z (gray and white with one chipped ear), and Invading Black Dragon Cham-P (orange and plump). Due to their territorial nature, Gundham used his body as a "bed" to tame them, so his left hand was always bandaged. San-D is an average-sized hamster with white and orange fur, dark-tipped ears, and pink hands, feet, and nose. He also has small black eyes and rosy cheeks. Jum-P is also an average-sized hamster with white and brown fur and pink feet, nose, and cheeks. Jump-P is usually seen with his eyes closed, a mucus bubble, and Z-shaped markings flowing from it, indicating that he is sleeping. Maga-Z is a fairly average-sized hamster with white and brown fur and one chipped ear. He has black eyes, rosy cheeks, pink feet, and a pink nose. Cham-P is a large golden hamster with orange fur, chubby cheeks, and pink hands, feet, and nose. He has small black eyes, rosy cheeks, and a pink mouth.

Gundham joined the Ultimate Despair after falling victim to Junko's brainwashing. Along with his corrupted classmates, he started The Tragedy and maintained it even after Junko's death in the final stage of the Killing School Life. Gundham and his classmates who did not commit suicide to follow their leader Junko soon became known as the Remnants of Despair. They also hacked into his body and grafted it onto themselves, although in Gundham's case, the specific body parts he took are unknown. One of his nefarious contributions as a member of the Ultimate Despair was leading an army of wild animals to help him spread despair and destruction. Eventually, the Future Foundation gained custody of Gundham and the other Fourteen, who at first only knew them to be survivors of Hope's Peak Academy. When Makoto Naegi, the Ultimate Lucky Student of the Class of 78, by then a member of the Future Foundation's 14th Division, realized that the survivors were, in fact, Remnants of Despair, he quickly led them to Jabberwock Island in secret. Makoto had them enter the Neo World Program, where their memories were reset to a time before they entered the Academy, before they were brainwashed by Junko, resulting in none of them recognizing each other. The plan was to overwrite the memories Gundham and the others had of themselves as Ultimate Despair, replacing them with good ones in order to undo all the damage Junko had done to them. The plan failed when Izuru Kamukura, Ultimate Hope, uploaded Junko's malware AI just before they were to be programmed. Consequently, they were subjected to the same brutal incident that befell Class 78, albeit in a realistically simulated environment. The killing game became known as the Killing School Trip, a test in which Gundham and the other Remnants of Despair were forced to participate.

Tanaka's kanji (田中) means "rice paddy" and "center," a generic surname chosen on purpose to make his irregularly read name, "Gandamu" (眼蛇夢), stand out. His name could be roughly interpreted as "snake-eye dreams." He is named after a Ramenman character who shares similarities with Gundham.

Gundham wears a long, black jacket that reaches below his knees and is always open, with a dark red interior; This is part of his old school uniform. He also wears a dog breeder's badge on the left side of the jacket. The left sleeve is rolled up to the elbow and secured to the jacket with silver pins. Gundham is also known for his long purple scarf, which circles his neck and covers his chin. Vertical symbols are printed on the back and ends of the scarf. Under the jacket, Gundham wears a white button-down shirt over a slightly darker shirt with a purple cross design on the chest. His black pants are tucked into strappy black boots. He has a crew cut, and the top of his hair is slicked back into a single curl. His hair appears wilder and more jagged when he is angry. His hair color is black with light gray streaks. Gundham has noticeably pale, grayish skin and no eyebrows. He has gray eyes, but wears a red contact lens in his right eye. The gray scar that runs across his left eye to his right cheek appears to be a tattoo. He is always seen with his hamsters, the Four Dark Devas of Destruction. The Devas usually camp inside the scarf Gundham always wears around his neck, but frequently appear during conversations or when he commands them to. Due to his territorial nature, Gundham bandaged his left arm with a single red bead hanging from the knot of the bandage, which he calls his "cursed arm," all the way to his elbow to protect his skin. Gundham's Hellhound Pendant hangs from his right ear, and he wears silver rings on the index and middle fingers of his right hand.

Gundham has an eccentric personality, stemming from his chūnibyō syndrome, characterized by his delusions of grandeur. As the "descendant of an angel and evil", he proclaims himself to be the personification of evil, someone who has claimed dominion over evil and thus a being that transcends humanity. To further embellish his villainous persona, he adopts bombastic titles such as the Supreme Sovereign of Ice and Tanaka the Forbidden. He also refers to his pets as his loyal subordinates under the rule of the Tanaka Empire and takes offense when others call his Four Dark Devas of Destruction "hamsters". Gundhams speak with an exaggerated, theatrical style reminiscent of a cartoon supervillain, using pompous, antiquated, and esoteric vocabulary, allowing him to inflate mundane interactions. His speeches, filled with poetic, cryptic, and metaphorical language and terms, often irritate and confuse others, especially those unaccustomed to interacting with him, eventually causing Gundham to push them away. He perceives "normal people" as lesser beings unable to grasp the magnitude of "his power," calling them "mere humans," "fools," and "demons," among other derogatory terms. In addition to being the "great and powerful Gundham Tanaka," he acts self-centered and aloof, withdrawing from others to focus on his own well-being and that of the Four Dark Devas. Although Gundham appears proud and avoids spending time with mere mortals, he seems reclusive. This is exemplified by his consistent attendance at the morning meetings at the restaurant.

Although he can be clumsy with other people, Gundham has a deep affection for animals, whom he often refers to as "magical beasts," and his pet "familiars." He states that anything he can speak will "eventually betray you," hinting at the possibility that others have hurt him before. This idea is supported in his Free Time Finale Events, where he accuses Hajime of being a "Kotodama user," a label he seemingly applies to those who try to manipulate him with "false words" and "cheap tricks," believing Hajime to be one and doubting his sincerity in calling him a friend. As a result, Gundham prefers to rely on the loyalty and sincerity of animals. Although it is only a rumor that he can speak to animals, what remains true and acknowledged by those around him is that Gundham truly understands the feelings of animals and is often seen with a gentler, softened expression and a smile when speaking of them. His empathy towards animals leads him to pity livestock for being raised for the sole purpose of human consumption. He is also very responsible towards the animals in his care, consistently providing them with plenty of exercise, high-quality food, and a good place to sleep, especially for the Four Dark Devas of Destruction amidst the killing game. He dedicates most of his cabin's space to their large cage and an extensive hamster tunnel stretched across the floor. His constant care and responsibility allows for the mutual trust and strong bond he shares with his pets, allowing for his commands to be heeded, be they hamsters, hawks, bears, or the notoriously difficult Pomeranians. However, his love for animals does not extend to anthropomorphic animal caricatures, which he finds highly offensive. This also extends to Monokuma and Monomi, as they "can talk" and, most importantly, are not "cute."

Gundham's official talent in the English translation is the "Ultimate Breeder". However, in the original Japanese version, the most literal and accurate translation is (超高校級の「飼育委員」) "Super High School Animal Breeding Committee Member", or in the Funimation subtitles, "Animal Breeding Committee Member". It is an after-school club common in many Japanese schools, dedicated to the care of animals (usually small birds, reptiles, and rodents) kept within the school compound. Gundham performed splendidly as a member of the club thanks to his ability to train and care for any animal, and his success in breeding endangered species. He revealed that his secret technique for taming animals is to start with the basics: chanting "Good girl, good girl", and making sure they understand that he holds no grudges. To achieve this, one must appear innocent and recognize which animals enjoy being touched and which don't. Then, he spends a good amount of time with them until he begins to listen to their words. Hajime comments that this must be something only the Ultimate Breeder can experience. Gundham has a natural aptitude for taming animals. A perfect example is his hamsters, the Four Dark Devas of Destruction, which he wears on his scarf and shirt. He put considerable effort into training them, allowing them to follow commands from basic to advanced (demonstrated several times during the Killer School Trip), such as retrieving small objects from high places, exploring an entire floor, and even sneaking up to press Mechamaru's Goodnight Button, rendering him immobile.

Gundham can't swim but only because he claims that "it's not very effective against water types" (referencing pokemon).