Kristoph Gavin / Kirihito Garyuu
Apollo's mentor in GS4.
If you turn "kirihito" to "hitokiri" it means "killer."
Background: Kristoph has been studying law ever since Phoenix's hay day in the original trilogy. He first met Phoenix seven years ago...
When famous magician Zak Gramarye was arrested for the murder of his master, Kristoph saw it as a great opportunity to advance his career. He approached Zak to take his case, and even decided to forge a piece of evidence that would be sure to seal his acquittal. He met with young forgery expert Vera Misham, and asked her to create for him a page out of Magnifi's journal that would implicate Valant instead of Zak.
To make sure that Vera wouldn't be able to implicate him later as having asked for forged evidence, Kristoph gave Vera a bottle of nail polish laced with a deadly poison. It ended up not working.
But before the trial took place, Zak insisted on playing a game of cards. Kristoph lost, and was fired as Zak's lawyer. It wasn't long afterwards that he learned Phoenix Wright was to take the case instead. In his anger for having been turned aside, Kristoph went to his brother Klavier, who would be prosecuting the case (his first case). He told Klavier that Phoenix intended to present a piece of fake evidence, and that if he wanted to catch him in the act he should ask the forger to testify.
The next day, Kristoph handed off the evidence he'd had forged to Trucy, with instructions to take it to Phoenix. She did so, and when Phoenix tried to present the evidence in court, Klavier was prepared with his witness. Phoenix lost the case, just like Kristoph wanted.
But then something happened Kristoph wasn't prepared for: Zak escaped custody and disappeared. Kristoph knew that if Zak reappeared, and if he told anyone that Kristoph had been his lawyer before Phoenix, everyone might find out that he had ordered the forgery after all. He tried to cover his tracks by sending to Vera a stamp also laced with poison, instructing her to use it when she sent back his receipt. But Vera escaped death again by deciding to save the stamp, which featured her favorite magicians, the Gramaryes.
Desperate to remain clear of suspicion, Kristoph began to spy on all the related parties that were left: he befriended Phoenix by defending him against the allegations of forgery, and kept tabs on the Mishams, as well as Zak's friend Spark Brushel. For seven years he kept a close eye on anyone who could potentially harm him, which all came to an end with Zak returned under the guise of Shadi Smith.