Agent Tsukino is an agent for the Public Intelligence Security Agency, a Japanese government organisation tasked with bringing down the Kuzuryu. Her first name is unknown. After her co-worker, Tesshin Asano, brought Logan to Japan to help bring down the Kuzuryu, Agent Tsukino joined Tesshin's team to spy on the house of Shingen Harada while Logan infiltrated the place. Logan however was drugged with a poison and subsequently defeated in a fight with Shingen, after which his unconscious body was taken away by Shingen's men. As Tesshin followed them to help Logan, he ordered Tsukino to remain at the house and continue to keep an eye on Shingen. She disobeyed him however, but when she caught up with Tesshin, Logan had already been rescued by Yukio.