Time has passed since that detestable event where she was completely defeated before a huge organization, and investigator AIKA has made a comeback. However, every time something happens, that day comes to mind... With revenge in her heart, she succeeds in kidnapping a young man from the Kuroshishi-kai as a stepping stone for a solo undercover investigation and interrogates him. But the huge organization Kuroshishi-kai also comes to AIKA's place to reclaim the young man... The battle between AIKA, burning with revenge, and the dark huge organization Kuroshishi-kai begins again!