- "Yesterday is history, today is reality, tomorrow is a dream. To me, tomorrow doesn't exist."
- —Yuuki Himura, in Pulling the Strings
Yuuki Himura is a major character in the series.
Yuuki grew up as a delinquent, and one that had to take responsibility for his siblings given that they never really had a family to rely on. Because of this, Yuuki grew into a responsible man at heart, but he disguises the care he takes of his siblings and those who come under his wing under a veil of innocence and naivety most people who know him figure to be false given understanding how he operates. He's quick to smile and laugh, and almost never seemingly is in a bad mood given how he chooses to pick his battles and understand what he's getting himself into beforehand. This, of course, is nothing to speak of those who are close to Yuuki and have to endure alongside him knowing that Yuuki is more liable to choose the most difficult route in order to test himself. That certain irresponsibility he has to him is often the cause that people have been driven away from Yuuki, but he's never minded it. In truth, he's always preferred his solitude, and asked nothing in return, but as fortune would have it, he was never so lucky as to entirely sever his bonds with other people.
Above all else, he cherishes his bond with his siblings, and would immediately die for them if he knew it would benefit them in some way. There is nothing in the world he wouldn't do for them, but he fears that the time when they've relied on him has come to an end. What he fears more than anything is becoming useless to them, which was part of his motivation for becoming a detective. While in school, he never had much time to spend with them, so he spends as much of his time as possible with his siblings, but he knows very well that if he were to leave them, they would survive without him. To keep himself tethered, he has bonds at his work place as well, but most of the police force that works alongside him somewhat fear his reputation as one of the most reckless detectives to have arrived in Inochikage City due to the risks he takes. They cite him as a brilliant mind, both sharp in terms of intelligence and wisdom, but also speak caution to those who work alongside him, claiming that the risks he takes may one day cause a death. Yuuki doesn't dispute these claims, but he fights as hard as he can to prevent that from happening.