Mikado Ryūgamine

Mikado Ryūgamine (竜ヶ峰帝人, Ryūgamine Mikado) is a childhood friend of Masaomi Kida and the primary male protagonist of the series.

Characteristics
Mikado is a polite, soft spoken boy, whom at times can be quite childish and naive. This is likely a result of his small town upbringing; as he moves to Ikebukuro he was amazed and overwhelmed by the sheer size and energy of the city, and thus himself felt small and insignificant. He was bored of the average life he had previously led, and moved to Tokyo in search of adventure. To he himself, he feels that his name (which translates as "Emperor of the Dragon Peak") sounds odd and childish, however it seems that some people think it is unique or just okay, like Walker and Erika.

Despite his personality, he is shown to have a fairly strong will, and he does have moments where he speaks out his thoughts (such as when he tells Anri she should be proud of trying to surpass Harima Mika), which is one of the reasons Masaomi admires him.

As he often acts like a child, Masaomi feels he has to stay around Mikado and help him out, since he would not be able to manage on his own. While Mikado often envies Masaomi for his exciting life (for most of the series he is unaware of Masaomi's affiliation with the Yellow Scarves), Masaomi ironically envies Mikado's innocence and his ability to lead a quiet, happy life.

As the series progresses, Mikado gradually becomes more and more assertive, and becomes able to accept the chaos that life throws at him without attempting to run away.

As shown in the light novels (and to a lesser extent, in the manga as well) Mikado has a much darker side to his personality. While he doesn't show it fully until the end of Volume 6, this darker half of Mikado is hinted at in various events throughout the light novels. The first example is during his confrontation with Namie, where Mikado voices his utter disgust with her in his mind while still keeping his timid personality on the outside. He also states that, no matter what the situation or whom is involved, whatever action or decision Mikado makes must also benefit himself in some way. In other words, self preservation and self satisfaction trumps all. This, by extension, means that almost every aspect about Mikado's life, be it his friends, family, or even Dollars, are merely entertainment tools to make his life more interesting.

While in this mindset, Mikado is much more ruthless and manipulative than he appears to be and is very capable at using intimidation to reach his goals. While it may initially seem like Mikado has split personalities, it is theorized by Aoba that the colder version of Mikado is his real personality while his timid side is the fake one. Izaya Orihara and Aoba both state later in the novels that they have underestimated Mikado.