Onna no Kokkai is a political mystery in which Kaoru Takatsuki, a legislator from the leading opposition party, investigates the death of ruling-party legislator Yuko Asanuma. Set in Nagatacho, it follows the intersecting motives of politicians, aides, and journalists as the background to the case emerges.

Troubled by the death of a fellow legislator, Kaoru Takatsuki follows the truth through the people of Nagatacho.