Inspired by Yukio Mishima, who committed suicide after a failed coup d'état among Japan Self-Defense Forces, Asada enlisted in the SDF after finishing his studies.
After graduating from Suginami High School, which is attached to Chuo University, he enlisted in the Japan Self-Defense Forces because of Mishima Yukio, though he initially denied this.
His novels often depict yakuza and it has been said that in this respect, they are autobiographical - Asada has admitted[citation needed] that he was once connected to a gang, specifically someone who ran businesses to raise funds for organised crime.
However, after winning the Eiji Yoshikawa Prize for New Writers for Metro ni notte (地下鉄に乗って) in 1995, his style and range of writing changed and expanded dramatically.
His historical novel The Firmament of the Pleiades (Sōkyū no subaru, 蒼穹の昴), which vividly described the last stages of the Qing dynasty, was nominated for the Naoki prize of 1996.
He wrote Mibu Gishi Den (壬生義士伝) based on the stories of the Shinsen Gumi (新撰組) and Ohara meshi mase (お腹召しませ).