Mentally dating fictional character
While he was only helping out and had no desire to be a detective himself, he learned to be a detective this way.
Shuichi's first detective case was unofficial but a tough one, as his classmate asked him to find her miniature pet alligator, and he had to do a lot of research, prepare tools and eventually climb around mountains and swim up rivers.
Most of the cases that happened to come to his uncle were small things like investigating infidelity, but on the one rare occasion Shuichi managed to solve a murder case faster than the police and became publicly known as the junior detective, gaining him his Ultimate title.
Part of the fake backstory created for Shuichi and the other fifteen students was The Gofer Project, which supposedly happened before the killing game started.
It was initiated by the government after countless meteorites crashed into Earth.
After he was accepted to participate in the 53rd Killing Game, Shuichi's memories were fabricated by Team Danganronpa.
Shuichi's parents are a famous actor and a screenwriter, who went overseas for business, which is why Shuichi began to live with his uncle and his wife.