しごとのむし
workaholic; person who is totally devoted to his work
Noun
彼かれのことを仕事しごとの虫むしだと言いうけれど、仕事しごとをしているときが一番いちばん楽たのしいという人間にんげんもいるんだよ。
You say he is a workaholic, but you know there are some people who feel happiest when they're working.