Abnar and his younger brother Adar are Delilah's personal Rephaim bodyguards. As they are practically spitting images of one another, the only way to distinguish them is by their apparel, especially their hats. They are skilled in the use of most weapons, including clubs, spears, and sabres, though it is is in hand-to-hand combat that they really shine as warriors.
After Branan knocks out Adar with his own club at the end of volume two, Abnar sneaks up behind Branan while he is sparring verbally with Delilah and cracks him on the neck with a bat. After several minutes of wrestling with the giant Abnar, Branan summons all the supernatural strength he can and tosses the Rephaim into some nearby pillars in Delilah's palace. At that point Adar regains consciousness, and he and his brother rough Branan up very thoroughly, then drag their victim to Delilah's dungeon as per their mistress's orders.
At the end of volume eight, Branan is given the opportunity for a re-match with the Rephaim brothers. When Abnar rushes at Branan with a spear and he moves out of the way, the spear ends up getting stuck in the wall. While Abnar is thus engaged with yanking his spear from the wall, Branan strikes his foe across the legs with a fighting staff. After regaining consciousness, Abnar grabs Branan by the hair and prepares to punch him, until Zarah takes her fighting staff to his head, then gives him a two-footed kick in the gut to knock him backward.
It is presumed that Abnar and Adar perish with their mistress and Lord Pathrus in the collapse of Delilah's palace at the end of the final volume.
Although tall and strong, Abnar and Adar do not come off as very intelligent and have been described as having "the combined intellect of a sand tick." Indeed, they seem to suffer from a form of aphasia involving the inability to form complete sentences.
Abnar and Adar appear to treat everyone with cruelty, even each other. Abnar, for example, claims Adar leaps "like a pregnant water buffalo," while Adar feels his brother lands on his opponents "like a dainty butterfly."