His novels often depict Yakuza and it has been said that in this respect, they are autobiographical - Asada has admitted that he was once connected to a gang, specifically someone who ran businesses to raise funds for organised crime.
Novelnya sering menggambarkan Yakuza dan telah dikatakan bahwa dalam hal ini, mereka otobiografi - Asada mengaku bahwa ia pernah terhubung ke geng, khusus seseorang yang menjalankan usaha untuk mengumpulkan dana bagi kejahatan terorganisir.