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. 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 weakling, who is terrified of other people being angry with her.

Here are some voice examples: https://youtu.be/ImOCymgLyB0