Chthon (Chthon #1) Book

Chthon was Piers Anthony's first published novel in 1967, written over the course of seven years. He started it when he was in the US Army, so it has a long prison sequence that is reminiscent of that experience, being dark and grim. The author regards this as perhaps the most intricately structured novel the science fantasy genre has seen. Aton's crime was simple. He loved a minionette. All worlds despised and feared this almost mythical siren but no creature anywhere could tell him why. In the brutally hot, subterranean garnet caves of chthon to which he had been condemned, Aton sought an answer. And when he could not find it--he determined to seek it elsewhere. No man had ever escaped Chthon and lived. But the minionette called. Aton had to have his answer. So did Chthon...