Reiji Mitsurugi is an esteemed prosecutor and an old friend of Ryuuichi Naruhodou. During his first four years as a prosecutor, he had a perfect win record, and he was a ruthless man who would do anything to get a guilty verdict for the defendant. This all ended when Naruhodou defeated him. Later, Mitsurugi became a defendant being represented by his "enemy", Naruhodou. After prosecuting in one more case, Mitsurugi left the prosecutor's office to find out what being a prosecutor really meant. He later returned and, by the time of the Mask☆DeMasque trials, had become known as the top prosecutor in Japan. He also traveled abroad to study international law, prosecuting in five other countries. As well, he was instrumental in finding the leader of a notorious international smuggling ring and bringing him to court. Mitsurugi is generally seen as a snob due to his skeptical, ruthless and generally aloof nature that differs little between everyday life and the courtroom. However, he has a strong sense of right and wrong, and acts only in ways that he believes are fair and just. He is also shown to care deeply for those he considers friends, going to great lengths to assist them when he believes they require it. For example, he chartered a private jet to come to Naruhodou's aid when the defense attorney was in desperate need of his aid. Mitsurugi is also very insecure in general and hates showing his weaknesses. Generally, Mitsurugi is calm and level-headed when talking with people, although he does tend to come off as a little cold and, sometimes, rather condescending. In court, Mitsurugi usually has the trial precisely planned out, ensuring his victory. Because of this, he tends to become easily ruffled with anything that does not conform to his plan. In particular, he tries to stick to standard courtroom proceedings, trying to make the witnesses state their names and professions, although he regularly has a great deal of difficulty with this task due to the often rather eccentric characters called as witnesses in his cases.