Kato Shigeaki joined Johnny's Entertainment on April 17, 1999 when he was 12.
As a junior he was a member of the organizations:
Best Beat Boys （B.B.B.）
Boys Be Ambitious （B.B.A.）
Best Beat Dancing （B.B.D.）
Beautiful American Dreams （B.A.D.）
He then debuted as a member of NEWS in 2003. Along with other NEWS members, he plays the guitar, composing some of NEWS' songs, including his own solo "Kakao" in 2002, which he composed the lyrics to. Other songs he performed solo are "Survival", "Happy Music" and "Shalala Tambourine".
Kato went to Aoyama High School and completed law school at Aoyama Gakuin University in 2010. He is an avid writer and writes his J-web entries from the perspective of a fictional cat named Wagahai. This is a parody of the popular book by Natsume Soseki entitled "Wagahai wa Neko de Aru" or "I Am a Cat". He also debuted as a writer with a novel "Pink and Gray" (published January 28, 2012).