natsu was in charge of the organ in the osaka band "grump leeds". after graduating from high school in the spring of 1969, he moved to tokyo after his professional debut with , who was a vocalist for grumpleys. yuki taura was added to the popular group sounds band "ox" at the time, taking over ai akamatsu, who left the group in may of the same year after being bought by horipro, the agency of wada.” in 1970, he changed his stage name to "yusuke natsu" while enrolled in "ox" and made his debut as a solo singer with "tears burning". at the same time, he entered the acting business and made his first movie debut with "". in 1971, the ox was disbanded at the end of may. while appearing in the tv dramas like "how about a beautiful woman?", natsu became a trainee of the theater company nlt.