Nepharim are larger, stronger, more aggressive, and less intelligent than nephilim. They are also more prone to demon-worship. Importantly, nepharim are sterile, a condition which makes it impossible for nepharim society to exist separate from nephilim society. Most nepharim are hostile to humans, but there are reported cases of friendly nepharim.
Most babies born to nephilim are nephilim. A small proportion, however, turn out to be nepharim. Exactly what causes this difference is unknown. Tentative studies conducted by researchers at Redmark College suggest that about 10% of babies born to nephil parents will turn out to be nepharim.
Relations with nephilim
Nephilim attitudes towards nepharim vary widely. Some tribes cast nepharim babies into the wilderness, leaving them to fend for themselves, and consequently to die. Others allow them a limited social role, exploiting or enslaving them as soldiers and guards. Less commonly, the two varieties of felines may live and work together cooperatively in the face of a common enemy, such as humans.
Many nepharim are resentful of nephilim as a result of this treatment. In the past, the constant persecution of the Empire had minimized the opportunities for large numbers of nepharim to congregate together. When many nephilim and nepharim were thrown into Exile, where they were not hunted and were mightier than many of the human settlers, this changed.
By 822 IE, a band of nepharim in the Eastern Gallery had enslaved a tribe of nephilim. Ironically, this was a catalyst for the first Human-Nephil treaty; Hawthorne's Assassins liberated the captive nephilim, who allied themselves with the Kingdom of Avernum in the Empire-Avernum War.