During the 2005 German federal election, Kumpfmüller became a member of an informal civic initiative founded by Günter Grass which supported the incumbent coalition of Social Democrats and The Greens.

From April to November 2006, Kumpfmüller was a literary fellow in six cities in Lower Saxony, writing and commenting on current events.

Far from beginning a new life, he continues his old lavish and promiscuous lifestyle, working as police informer for the Stasi and dealing on the black market.

The book's protagonist Heinrich Hampel serves as a symbol for the complexities of inner-German relations in times of the Cold War.

In 2003 Kumpfmüller published the novel Durst (English: Thirst) about a woman who abandons her two children in the midsummer with only a small juice carton left in the apartment.