Tokunan Seiichirou was the eldest of 8 children. He was plagued by illness in his early childhood and stopped growing at 1.40m, which led to relentless bullying in his school years.
Dreaming of becoming a mangaka from early on, Tokunan was eventually given a shot by the local kashihon publisher Toukoudou. His debut work "Kage wo kiru Samurai" (影をきる侍) appeared in 1955.
However, his books were unpopular and soon he found himself trapped in a vicious cycle of commercial failure, work pressure and personal problems. This led to his stories becoming increasingly bizarre and his art increasingly sloppier, which in turn would result in even less success. By the time his best known work, Human Clock, was published, his books were frequently returned to bookstores by unsuspecting readers.
In 1963 he turned his back on the manga world for good.
Interest in him resurged in the 1990's when Ohta Shuppan reprinted Human Clock, but Tokunan himself remained elusive.
He passed away on 24th December, 2009.