K1-B0

Appearance
K1-B0 is a robot, therefore having a fully mechanical body structurally engineered to, in shape, resemble a human being. His body is mostly made up of metallic, armored plating, not wearing actual clothing, but resembling a gakuran, a school uniform worn by male high school students. He has four glowing buttons that run from his chest to his stomach down the middle of his torso, a metallic left breast pocket, and something that resembles a belt around his waist, two red buttons attached.

As a robot, K1-B0 is considered sexless and lacks the means to have reproductive functions, but still appears masculine physically and has the voice of a teenaged boy. His face has very pale skin. His eyebrows press closely to his round, mechanical blue eyes, making it appear that his brows are a part of his eyes. Thick black lines run from around his eyes and down his cheeks to reach his chin. He can make his eyes glow a bright yellow or blue and emit light. He has a tongue, but it doesn't seem to have any other purpose than speaking, as he cannot actually eat food. He has white hair that is very sharp and swayed to the left, along with the very large ahoge on the top of his head.

K1-B0 possesses a very tall, round and metallic collar around his neck, his previous school's emblem on the left side of his collar. A thin strip of screen wraps all the way around it, displaying a constantly changing string of green text. A softer black material covers his neck entirely, but he is capable of moving it up to cover the lower half of his face to resemble a face mask. The collar is usually open in the middle, but is able to clip the two metallic parts together to protect the area of his neck entirely. He doesn't seem to have actual ears, but black, headphone shaped objects in the area around them. He can use his ears to take recordings and play them out loud.

Personality
K1-B0 is a polite and serious teenage robot, who has some trouble with human social interaction, and often comes across as unintentionally comical as a result. According to Kazutaka Kodaka, K1-B0 has both cute and cool characteristics, with him being socially awkward but serious. Nevertheless, K1-B0 takes pride in his form and often boasts about his wonderfulness and efficient functions, though the other students never seem to find them impressive much to his disappointment. His aim is to overcome being an ordinary robot and because of this, he may get offended if he is compared to much more simple machines. While generally well-mannered, he is quickly angered by any prejudice against robots and sometimes threatens to sue people who make "discriminatory remarks". He considers robots a minority group among humans and can get slightly paranoid about "robophobia", supposedly because of past experiences. However, ironically, he himself is shown acting condescending and perpetrating "robot-on-robot abuse" towards simpler machines such as the robots with Monokuma's likeness, considering them mere stuffed animals who are beneath him.

Since he is a maturing AI, K1-B0 learns and develops similarly to a human, making him an unique existence. While he has no heart nor brain, he uses his calculations to speak "as if he had a heart". Even still, he often can't read the mood around him and is oblivious to things, sometimes taking things very literally and occasionally acting insensitive. Due to being overly serious about certain topics and unable to understand sarcasm, he is an easy target for bullying and it's easy to make him heated up, and he is rather easy to read. According to Izuru Kamukura in the bonus mode Ultimate Talent Development Plan, K1-B0 has a tendency to rely on others in difficult situations, and he overall gets very nervous in bad situations. Furthermore, he feels a bit self-conscious about the fact that he cannot strengthen his body on his own like humans, and he needs help for maintenance and upgrades. Overall, he is a bit conscious about being unable to do some things humans can, causing him to act condescending towards humans at times and proclaim that he can do lots of things humans cannot. In Chapter 4, when the students enter the program world, K1-B0 appears disappointed and secretly wished he would have a human body. In Chapter 5, he is seen wondering his existence and being very interested in whether or not he is considered a person by the hydraulic press' safety function and Miu's Electrohammers, and even wants to test them despite the risk. In one scene, he is scared of the idea of a huge mecha suddenly appearing, not realizing the irony of it. He himself has also pointed out that he doesn't really like "sci-fi" things, even though his existence alone is quite sci-fi, and he would rather be more like other people instead of possessing things like rocket jets. He greatly loves Japanese culture, including Japanese food (though he can only look at it), kimonos and wind chimes. However, he also feels insecure about being too ordinary and not deserving his title as the Ultimate Robot, which is why he has a dream of becoming a pop star or doing some other type of work. For a short time, he even considers becoming a "tragic hero" figure in order to become more interesting, with a new tragic backstory and weapons, even though it's not something he would like. In general, he has a strong desire to be accepted and be like everyone else.

K1-B0 seems to understand most human emotions and many of their habits, though some of them only in theory, and he prefers to make decisions and actions based on logic. He claims that he works very hard every day to understand human emotions, and he's often quite hurt and saddened whenever the other students tell him that he wouldn't understand something because he is a robot. He tends to find abstract ideas frustrating and difficult, and sometimes has a hard time understanding why someone would do something that is very illogical. In general, he can get confused and a bit uncomfortable by his strange classmates, and sometimes reminds them to speak in a way he can understand. He can also get some habits a little wrong, like confusing the action of handholding and handshaking. Like a human, he blushes when he is feeling shy and feels awkward when talking about something inappropriate, though occasionally he may say inappropriate things without realizing it due to his naivety. For example, he considers nudity very shameful and embarrassing, but doesn't seem to see anything inappropriate in going to the bathroom, as he sometimes casually tells his classmates they're free to do that if they are close to a bathroom or even telling them they can do it right there even if they're in public surrounded by people, seemingly trying to be polite with this gesture. He can be very expressive with his body language since as a robot he can move his ahoge and some other parts according to his emotions. Being a robot, he is also very innocent when compared to most teenagers, and some situations make him very nervous and shy. In Chapter 3, he claims he is ticklish and it's implied that he might be able to feel pleasure similar to sexual pleasure when sensitive spots underneath his armor get touched. In general, he doesn't seem to have very much interest in sexual matters, considering it quite scandalous and claiming at one point that he would never expose Professor Idabashi's strong AI to pornography. He has also bashfully pointed out that there isn't much he can do about it anyway, since he lacks any reproductive functions. However, he secretly seems to have some interest in such subjects, as he once accidentally admitted this without thinking. When he is asked about his ability to fall in love, he says he doesn't know because he hasn't had any romantic feelings yet. In the bonus mode Love Across the Universe, it's eventually confirmed that he can fall in love and dreams of romance and intimacy. In the topic of romance, K1-B0 is shown to find the idea that robots should only date their own kind very offensive. When he does develop romantic feelings, he is shown to be very serious and surprisingly bold about the matter, assuming that you constantly have to do typical things couples do and be very dedicated in order to truly understand love. However, he is simultaneously very shy about the subject, as he gets very embarrassed, blushes a lot and stutters when he just asks to hold hands. He also seems to consider the maintenance Miu performs on his body very intimate and he is very embarrassed about it at first, especially if it's mentioned in front of others, as if it is a sexual relationship (though, it does resemble one). While he doesn't speak to Miu in explicitly romantic manner, he does care about her a lot and even gets jealous of a computer.

Overall, K1-B0 appears to be quite well-meaning and kind, and he genuinely wishes to be friends with everyone (even considering Kokichi his friend during the bonus mode). He has mentioned multiple times that he wishes to make people smile and happy. He even likes comedy movies, because he enjoys the feeling of people having fun and wishes to become a robot who can make lots of people smile someday, like a comedy movie. He is also pacifistic and refuses to hurt humans, greatly respecting the First Law of Robotics, and in general dislikes violence and weapons. He also dislikes certain action movies for the way they portray robots as evil and murderous killing machines, considering it robophobic since most robots are friendly to humans. During the bonus mode, when Shuichi suggests making their own movie, K1-B0 would like to make a drama about hero stuff, which would be popular with children. K1-B0 wants to be the fearless hero while Shuichi would be the innocent citizen he saves from a villain. In Chapter 4, he even has some empathy for those he dislikes, as shown despite his grudge against Monotaro, he feels regret for Monotaro and Monophanie dying a terribly disturbing way and is upset at Monokuma for unsympathetically killing them like that.

K1-B0 often serves as the butt of jokes and is rarely taken seriously by the other students, which isn't helped by his somewhat wimpy and oversensitive personality, but he gets increasingly confident throughout the game and begins to motivate others and talk about hope and defeating despair, especially after remembering Hope's Peak Academy. During Kaito's execution, he even leaps forward to protect his friends with his more durable body. Furthermore, with his logical way of thinking, he quite often makes correct arguments and points out important things, not letting feelings cloud his judgement. He is willing to approach even unpleasant topics, such as the possibility of Gonta being the murderer, for the sake of reaching a logical conclusion and he tends to stay calm and sensible whenever most other students get too emotional to argue properly. Some of this could be a result of his "inner voice"—voices inside his head that guide him in difficult situations. He decides to listen to them more firmly after hearing Angie Yonaga's talk about God, treating his inner voice as his God who gives him advice and cheers for him. When he's mocked for being a robot who believes in God, he says robots can do that. When his ahoge is broken by Kaito's execution, the voices go silent, causing everything to become "too quiet" for him and forcing him to use his own logic. It's later revealed that his ahoge is actually an antenna that receives information from Team Danganronpa, which will take the form of an "inner voice" and persuade him to take certain actions, said actions being decided through viewers' surveys.

Backstory
Professor Idabashi, the leading expert in robotics engineering, created K1-B0 to be the culmination of all his research and work. He was meant to be a robot more human than any other robot before. Initially, K1-B0 had no knowledge nor awareness, and was only capable of displaying a very narrow spectrum of human emotions. The plan was to raise and develop him like a parent would their own child. However, a few years passed, and there was no improvement in his mental state.

One day, an unpredictable accident occurred during a routine experiment. K1-B0's programming went rogue and he ended up seriously maiming the professor, but fortunately he survived. After hurting the professor, K1-B0 was suddenly overcome by immense sadness, especially considering that the First Law of Robotics stated 'a robot must not harm a human being'. Even though K1-B0 wasn't punished for breaking that rule, he nevertheless felt sadness and blamed himself, feeling extremely guilty. For the first time, he understood how it felt to feel human emotions, and at that moment his AI suddenly reset as if committing suicide. He became similar to a newborn infant once again, with all of his memories deleted. In his "next life", K1-B0 called it the day of his own "death" and the day of his true "birth". After learning the story from the professor, he assumed that perhaps he had wanted to be "reborn" as the professor's son once again.

K1-B0's strength was considerably weakened after the incident, described as being similar in strength to an average senior citizen. This time, his AI matured accordingly and he learned and developed as his creator raised him like his own child, with K1-B0 considering the professor his father. Eventually, the professor even sent him to attend Īdabashi Industries High School (飯田橋工業高校) and he was recognized as being Ultimate even as a robot. However, he fears that other students will discriminate him because he is a robot.