Nef was a member of the Bat Clan and the Soul Eaters; however, she seemed to retain more feeling and compassion than the others (though, as Torak notices, this doesn't make her any less grounded in the ways of the Soul-Eater). Her thoughts flew faster than a bat. She loved to enchant small creatures to do her bidding. Nef sincerely believes that everything that the Soul Eaters are doing is for the greater good unlike Thiazzi, Seshru, Eostra or Tenris who all only believe in ruling the Forest. This is likely due to the fact that she lost her son to sickness early in her life. After the loss of her son, she was filled with such sadness that she wanted to commit suicide but Torak's Father helped her get over this sadness, thus stopping her from killing herself.
Later, during the events of Soul Eater, she jumps into a crevasse in the ice river of the Far North, with a piece of the fire opal in her hands, to show her thanks to Torak's father for saving her. This resulted in the Demons that had been released from the Eye of the Viper following the light of the fire opal into the ice, where they would be trapped forever; and due to the particles of rock in the ice, the piece of the fire opal was extinguished.