木山裕策 was born on October 3, 1968, Osaka. He has a wife, 4 kids and is currently working as a publisher. Yusaku was once part of a band in college. His major music influences were BILLY JOEL, Miyuki Nakajima, and Masayoshi Yamazaki. In 2006, he was diagnosed with having a tumor in his left thyroid. At that time the doctor warned him that he might lose his voice if something went wrong with the surgery. Yusaku was alright with it saying: "if i do get a voice after the surgery, i think i will never sing again"