Nusito were a kind of domesticated animal.
A tribe trained their elite troops by giving them a nusito pup when they entered the cadet program. The troops were encouraged to bond with the pup, even racing theirs against other troop's pups, eventually leading to the troops loving the nusito pup. Before the cadet could graduate, he was ordered to strangle his pup or be kicked out of the program. The cadet had to be able to place duty before emotion.
Behind the scenesEdit
The concept of a cadet raising and eventually killing their nusito pup is, according to Karen Traviss in the Round-Robin Interview included in the back of Legacy of the Force: Inferno, an allusion of the test that was used by the real-world German SS/Gestapo. Karen says "I mentioned a test that the German SS (or it might have been the Gestapo) used: trainees were each given a puppy—a German Sheperd, I think—and were encouraged to bond with the dog, compete it against other cadets' dogs, and generally love it. Then, once they were totally devoted to the dog, they were told to strangle it. If they couldn't obey that order, they were out. I said that would be a typical Sith test—to be so loyal to the Sith ideal that you'd obey orders and kill someone you loved to prove you could put the job first. There's even an allusion to that in Legacy of the Force: Sacrifice, where Jacen thinks about the nosito[Sic] pups."