Tokyo ghoul’s Kishou Arima was one of the anime’s most memorable characters. He was a force to be reckoned with. A powerful presence and a foe no ghoul or agent wanted to have to deal with. Arima for all intent and purposes seemed to have it together. So why did he kill himself?

When we first meet Arima he is attending Kureo Mado’s funeral service. He reprimands his fellow agent Itsuke Marude for speaking ill of Mado during his own funeral giving us a glimpse into the kind of man he is.

Arima is later seen numerous times on missions, demonstrating why he has been hailed as a genius since his teens. His mere presence is typically enough to scare off most foes and his prowess in combat makes him almost invincible.

Through out the anime’s run, few if any have been shown to be able to keep up with him. He’s pretty good looking as well and most agents seem to respect and even look up to him, so the last thing anyone would expect is that he would kill himself.

In order to understand Arima we will have to delve deep into his mindset, what he was thinking and the guilt that has burdened him for much of his lifetime.

As the story progressed we discovered Arima was the famed One eye king, something that very few people expected given his status in the CCG, but it’s facts like this that give us insight into the man and exactly what was going on in that head of his.

See, Arima had a pretty difficult childhood to say the least, and though he was lucky in many ways, growing up was not easy. He joined the CCG at a rather young age and even then his skill and ability was apparent.

This coupled with his youth resulted in him taking on numerous missions that most agents typically couldn’t. It was during his high school days he would meet and partner up with Taishi Fura and the two would go on numerous adventures killing ghouls in their ward.

It was also around this time that he would encounter Eto, sparing her life after defeating her and discovering her intentions of building a better world. Arima and Eto would then begin working together in secret.

It is apparent from most of his decisions and actions here that only one thing has been of major importance to Arima, protecting innocent lives. He being a half ghoul placed him in a unique position, allowing him to see both sides of the conflict and understand where everyone was coming from, much like Kaneki.

That said one can only imagine the guilt that racked him every time he had to take a life, even if it was the life of a ghoul, as someone who truly understood the conflict and as a half ghoul himself it couldn’t have been easy, yet he no doubt shouldered on for the sake of the mission he and Eto had.

A mission to forge a world where all the killing could stop. It was for this reason he invested so much into Haise Sasaki (Kaneki) mentoring him and preparing him to eventually take his place.

This is a big part of Arima’s psychology. Though many hailed him as a genius, for him it would all be meaningless if he couldn’t achieve anything beyond the act of taking lives.

In his eyes, it was not a trait to be glorified or praised, but one appalling to say the least. I imagine that might have been why he took such a liking to Kaneki. I imagine in many ways he might have seen himself in the young man.

So in the end the question remains; why did Arima kill himself? Arima killed himself because he was tired of a world in which he was glorified for something he hated. Arima did it to forge a new world, a world in which humans and ghouls could live without looking over their shoulders, constantly. He did it because it was his duty as the One eye king.

Aside from that Arima was already dying, his accelerated aging meant he was unsure when his biology would suddenly fail him. Arima killing himself, was him ensuring that when he did die, he would have left something meaningful in this world.