Miu Iruma

Miu is described as an oddball, having an overly confident, loud personality and a frighteningly sharp tongue. She considers herself a beautiful genius, and every time she opens her mouth she spews a parade of reckless vulgar remarks and insults, strongly putting pressure on others and looking down on them. She also tends to give other characters insulting nicknames, and would routinely call them virgins. This is also reflected in her speech, which bears an extremely thick Kansai drawl to it.

However, Miu's arrogant personality seems to be only a mask that can drop fairly easily. This often happens when her festival of coarse language and dirty jokes actually get replied to or ignored. Then, her personality quickly changes into a timid coward, who is terrified of other people being angry with her. Because of this, she has a charm similar to an innocent child.

As an inventor, Miu is skilled but also an eccentric who treats her failed projects with the idea that "I transferred the rights to the company, so it's got nothing to do with me". She has made all kinds of amazing conveniences, but only deems her inventions as a success when they help the user to perform a task while sleeping (it's possible this is because she suffered from a coma in the past). She also has a habit to make very bizarre, seemingly pointless inventions which are sometimes very sexual in nature, including a "Hookup Counter" which tells how many people you've had sexual intercourse with, an "Auto-Puncher that Punches You for Telling Terrible Dirty Jokes", and a "Goin' Commando Gun" which can teleport underwear and only underwear. Even seemingly innocent inventions such as Electrohammers and Electrobombs can have dirty innuendos. Nevertheless, Miu has also used her remarkable talent to make very useful inventions as well, though in most cases they were concepts created and requested by others or something she created because she was bored. It is also shown that as an inventor, she firmly believes in science.

Miu comes off as very perverted and openly says bizarre, obscene things during her arrogant moods, meaning almost constantly. She often claims that she just says them to lighten up the mood, but they are very much disliked by the other students. Despite often trying to act dominant and appear sadistic, Miu is also masochistic and into BDSM, and acts very different during her weak-willed moments. Despite her usual arrogant behavior, she seems very uncomfortable if other people actually act very submissive towards her, though she later claimed that such situations turn her on.

Despite her penchant for calling others virgins, openness about her kinks, and tendency to make obscene remarks, it is suggested that Miu actually is a virgin herself; it is impied that her own love life is unsuccessful, if not nonexistent, and she gets extremely defensive when someone suggests that she is a virgin. In bed, Miu awkwardly gives others permission to have their way with her, suggesting that in spite of all her sexual comments and jokes, she has never faced a serious opportunity for sex. It is also suggested that she wants love and not just sex, thinking of it as based on a childhood friend romance. She would also insist on being offered a romantic gesture before going further. Lastly, Miu becomes lovesick for others because they stopped her from killing herself, suggesting that she would fall in love with anyone who is at least somewhat affectionate towards her.