Feyd-Rautha Harkonnen is nephew to Baron Harkonnen, and is groomed to be his heir. Feyd-Rautha’s position is similar to Paul’s, and his character operates as Paul’s alternate. Both boys are the same age, born to powerful families, groomed for leadership, and prepared to be capable and powerful fighters. However, while Paul is raised on the relatively moral or neutral teachings of his father and mother, Feyd-Rautha is raised on his uncle’s twisted worldview, which includes consuming as much wealth as possible, acting without mercy for one’s own gain, and treating sex as an act of violent domination over another human being. Consequently, Feyd-Rautha becomes a violent, calculating person who is completely apathetic toward other human beings, including his own Baron uncle. He is, however, an intelligent and physically impressive man, and Count Fenring remarks how unfortunate it is that Feyd-Rautha was born to such a cruel House, as he may have reached a greater potential if born to a more reasonable House like the Atreides.

In particular, Feyd-Rautha enjoys fighting and violence, and engages in gladiator-style battles against drugged slaves for the entertainment of the Great Houses and the public. He is also sexually active from a young age, indulging in enslaved prostitutes – a behavior likely learned from his uncle. He does not seem to have a concept of romantic partnership beyond possession, referring to Chani as Paul’s “pet.” The Bene Gesserit take advantage of his lustfulness to further their own plans, having Count Fenring’s wife seduce Feyd-Rautha so that she can bear his child. So, while Feyd-Rautha and Baron Harkonnen are killed by the Atreides at the end of the novel, Feyd-Rautha’s genes – and therefore House Harkonnen – technically live on, although the child will be under the control of the Fenrings and the Bene Gesserit.