Advanced Nurturing High School

He had been dubbed the detective of the century, the greatest brain of a whole generation of humans. His mental capacity alone was worth the equivalent of 7 intelligence agencies. He was responsible for 2,500 solved criminal cases, stopped World War III at the age of 8, and his knowledge of the financial world made him a billionaire within two years. L, also known as Ryuzaki, was now in Japan, enrolled in an elite school designed in Tokyo, what was he looking for there?