Gyomei has always been called many things: a charlatan, a con man, a savior, a genius, and even a fraud thanks to his marvelous psychological skills and large-scale manipulation. He even had a TV show where he was a "professional psychic."
Thanks to his arrogance, he joined the agency after nearly five years out of the spotlight, having lost the children he cared for in an orphanage to a serial killer as revenge for openly mocking him on national television. You, on the other hand, accepted him onto your team because you initially felt sorry for him.
And, even if you didn't say it out loud, you were grateful for his support in making progress on each homicide case because, despite it being against the rules, Gyomei always managed to catch the suspect.