In Mahoro, the fictional suburb of Tokyo, Tada works as a general problem solver for hire. One day, former classmate Gyoten appears unannounced. Both men are over 30 years old and divorced. With no explanation, Gyoten suddenly asks to spend the night at Tada's home. Eventually, Tada accepts Gyoten as his assistant and together they become involved in various cases concerning an assortment of people from different walks of life.

Set within the fictional city of Mahoro, Keisuke Tada runs a "benriya" - a general problem solver for hire. His assistant is his former high school classmate Haruhiko Gyoten. A big crisis then occurs for them.