Nitta is a young man who wears silver framed glasses, a deep blue jacket, necktie, pinstripe shirt and white chino pants.
Nitta and Saruwatari were never very close, but they were batterymates in their high school baseball club. One day they had a match and worked together well, but it still ended in their loss. Saruwatari, angered by this and Nitta’s apparent indifference, punched him in the face. The two would never meet again until Satuwatari arrives in Fukuoka seven years later.
More recently, as a Killer Consultant, Nitta offered his services to George Gondo. He advised him to pose as the infamous killer known as G.G. in order to quickly earn huge sums of money, which Gondo needs in order to pay for his daughter’s medical treatment. Nitta still contacts Gondo to take on jobs.
Light Novel Volume 2Edit
Nitta encounters his old acquaintance, Saruwatari not long after he arrives in Fukuoka. Although Saruwatari does not immediately recognise him, it turns out that the two were batterymates in their high school baseball team. After the two head out to get something to eat, Nitta reveals that he is a Killer Consultant, and offers his services to Saruwatari, promising to make him the number one killer in Fukuoka.
The next time they meet up, Nitta begins to offer advice to Saruwatari about how he can make a name for himself, namely, by choosing a signature weapon. He specifically recommends ninja-like weapons, urging a reluctant Saruwatari to practice throwing shurikens.
Some time later, Nitta gives Saruwatari the task of hunting down two or three killers, giving him a list of killers operating in Kitakyushu City. He is shocked, however, when he calls Saruwatari to find out that he had killed all but one. Nevertheless, Nitta assures him that this is a good thing, since having an eyewitness will mean that rumours of Saruwatari will start spreading.
Later, Nitta asks Saruwatari if he will do try outs for the Kakyuu Group. He does so and lets a shocked Nitta know that he has been given the job of killing the Niwaka Samurai. Nitta immediately searches for any information regarding the Niwaka Samurai and happens upon undergroundjobs.com. There, he finds a listing which is apparently made by the Niwaka Samurai, who is looking for jobs to take on. He immediately suspects this is fake. Even though Saruwatari agrees, he decides to contact them anyway. While Nitta does not stop him, he does believe it is a waste of time.
After meeting up with a second fake Niwaka Samurai (who he believed to be real this time) and having him and his money taken away by Abe and Yamamoto, Saruwatari calls Nitta. They meet up and Nitta helps track them down by using the tracking device Saruwatari placed on Abe and Yamamoto’s van. After locating them, Nitta decides to go there with Saruwatari.
Upon reaching the location, Nitta and Saruwatari confront Abe and Yamamoto, taking back the stolen money but also discovering the body of the supposed Niwaka Samurai. Upon finding out that this one is also a fake, Nitta presses the two for information about the Niwaka Samurai’s mediator. After this, he decides to use the fake Niwaka Samurai as bait to lure out the real one.
The next morning after Saruwatari’s first battle with the real Niwaka Samurai, Nitta meets up with Sayuri, who had called for him to meet her at a hotel. She had just finished her job of killing the president of the Kakyuu Group and Nitta aids her escape by giving her a hotel employee uniform. He then goes on to ask Sayuri if she will carry out a request he had received from a woman in prison, however she declines. It is not long before he decides to contact the killer George Gondo, who accepts the job Sayuri had declined. It turns out the request is to kill Saitoh.
Later, Nitta calls Saruwatari after worrying that he had been killed by the Niwaka Samurai.
- Nitta gave Saruwatari the nickname "Sarucchi" because he tuts ("chi") a lot.