Miu feels irritated by Kokichi's behavior and believes that he is the mastermind. She is shown being annoyed by his lies multiple times and insults him by calling him a shota and a compulsive liar (in the English version, she goes even further by calling him "lying little abortion"). Kokichi's behavior towards Miu ranges from teasing her to outright insulting her or making fun of her. He is shown to be very mean-spirited and nasty towards Miu, often calling her by derogatory sexual terms like "a whore", "a bitch", "pig" and "bitchlet", and later into the game he even calls her "Cum dumpster" (肉便器 Nikubenki - lit. Human Toilet, used as a strong derogatory sexual term for promiscuous women/兼餃子 Ken gyōza in the Japanese version), and stating that she's things like ugly, smelly and useless. He also often calls her a pervert due to her sexual nature or makes dirty jokes at her expense. Kokichi's treatment of Miu seems much harsher than with anyone else as he quite often appears more serious while insulting her, though being a masochist Miu often just enjoys the insults, appearing aroused. The two are seen insulting each other multiple times during the trials, with Kokichi winning these debates due to his stronger personality and Miu's cowardly tendency when talked back.
In Chapter 2, Kokichi witnessed Miu in the dark, walking around in her underwear in the courtyard, as a tactic to escape Gonta. During the investigation, Kokichi told the others about the situation and how strange it was, with him appearing visibly displeased. He later mocks her during the trial for being perverted.
In Chapter 4, Miu tried to convince everyone to enter the virtual world she made, claiming it was a safe new world for the benefit of everyone, and ordered them to bow down to her as their new savior, but Kokichi told her that she should be the one bowing since she is the one asking for something from them. Unlike in many earlier situations, Miu looks very uncomfortable and appears depressed after obeying Kokichi's command. This exchange is illustrated by the only two CGs in the game that feature a completely different art style. In the first one, Miu is seen crying while looking at Kokichi, who is watching Miu and giving his back to the viewer. In the second one, Miu is seen bowing on the floor, pleading to be heard while Kokichi and everyone else is looking at her, but his eyes are obscured by his hair. This sequence is a popular Japanese pop culture reference to the manga "Slam Dunk!" in which a character named Mitsui is moved to tears by the appearance of his coach, breaks down and cries while admitting that he wants to play basketball.
Later, while inside the virtual world, Miu tries to follow through with her plan of murdering Kokichi by inviting him to meet her on the roof of the Hotel, and placed a bottle of poison on his chair before logging into the game to make it seem like he died by being poisoned from the outside. Her plan entailed altering the game's code by changing Kokichi's avatar settings to instantly paralyze him if she were to touch him, rendering him defenseless, and deleting all harmful objects and weapons except for a hammer she was planning to use on him, which would have caused his real body to die from shock. However, Kokichi having already figured out her plan, avoided his own death by luring Gonta into killing Miu by strangling her with a roll of toilet paper. Later, after Gonta was revealed as the culprit, Kokichi stated that he would have done it himself if he could, but Miu's settings prevented him from defending himself. He told Monokuma to execute him as well, stating that he came prepared to die, which could imply he felt guilt, but he appeared to mostly feel bad for Gonta instead of Miu. Despite her murder attempt, Miu claims to have no particular ill-intent against Kokichi, as seen in Kokichi's flashback of the attempted murder, where she was shown looking nervous and apologetic.
In chapter 5, Kokichi appears in front of the other students with a multitude of bombs and weapons that bear Miu's distinct aesthetic and colors. It is revealed by Kokichi that those are weapons made for him by Miu before passing away. He explained he had a conversation with her some time before chapter four happened, where he presented some blueprints to her and asked her to build various inventions to fight Monokuma and the Exisals. While Miu agreed to create the inventions, she explained that she wouldn't cooperate with the others because she believed there would inevitably be a betrayal. Though refusing to fully cooperate, she asks Kokichi to come back to save her if his plan turned out to be successful, offering her body to him as thanks while blushing. Kokichi listened to her words seriously and later appeared to feel genuinely bad for her when he told the others about the conversation.
In the Anthology Series Miu and Kokichi accidentally swap bodies by bumping into each other in Volume 3, Chapter 8 titled, "Did we just..." by Yukiya Tomoki.
The two decide to act like each other in order to prevent the other students from realizing that they had swapped bodies. (Although it is later revealed in the end that Maki and Shuichi had realized).
Kokichi (in Miu's body) ordered Miu to fix their situation as soon as possible, blaming her for bumping into him, stating that he did not enjoy being in her body, calling it filthy and worrying about the idea of being stuck there in case either of them got murdered.
As Miu researched in the library, Kokichi waited for her in her lab. However, he gets an unexpected visit from K1-B0, who asks him to perform maintenance on him, believing he’s talking with Miu. Kokichi, having no choice, agreed, but only managed to break K1-B0. He realizes how hard it actually is to invent things and perform maintenance on K1-B0.
Meanwhile Miu (in Kokichi's body), who is having trouble reaching the highest shelf due to Kokichi’s height, suddenly gets lifted up by Gonta as he attempted to help. Surprised, she lashed out, telling him he shoudn't pick up a woman all of a sudden like that. This outburst attracts the attention of Kaito who was walking by and he stops to chastise “Kokichi” (actually Miu) about not messing around with Gonta, jumping to the conclusion Kokichi had manipulated Gonta into helping him again. This made her realize how much the other students automatically mistrust and blame Kokichi, sometimes unfairly.
The two at last finally manage to switch back into their own bodies, and as Kokichi was about to leave, she stops him to say she realized he has it rough and blushed as she offered to lend him her chest (body) whenever he needed to. Kokichi, facing away from her, replied that he also acknowledges that she has to put her head to good use at times (referring to how hard her talent is), stating that his opinion of her had changed, but only a little.
The ship sailed as a result of Kokichi constantly mocking Miu, which some fans like to interpret as mocking one's crush. This was even more of a reason because Miu actually enjoyed being insulted with some of the nicknames, such as "cum dumpster". The duo having important interactions later on, with Miu creating devices against Monokuma, his kubs and Exisals for Kokichi and planning a murder for him but instead being outsmarted by him has also helped. Many also believed that if Kokichi and Miu were to meet under different circumstances, that they'd actually get along.
- Kokichi's relationship with Miu on Danganronpa Wiki
- Miu's relationship with Kokichi on Danganronpa Wiki
- This is the second Danganronpa ship between a victim and a person whom they targeted to kill before their death but failed, with the first being Leosaya.