Issa has the fangs and hood of a cobra, but the beautifully angelic face of a woman. Her torso is human, with perfect globular breasts. Like all Naja, she does not wear any clothes. Instead, she decorates herself with snakes. Below the waist, she is of serpent aspect.
Issa is wise and sweet, fiercely loyal to Brimstone, Twiga, Yasri, and Karou. However, she also displays a vindictive streak, such as when she gives the despicable tooth trader Bain an irritable snake to wear as a collar. Though not a warrior by any means, Issa is shown to be quite capable in combat when she kills Ten, in Days of Blood and Starlight.
Issa has served Brimstone for over 84 years, so she must be far older than that. Issa's background and blood family have not been explained.
Daughter of Smoke & Bone
Issa is the guardian for Brimstone's shop. Whenever a customer looking for Brimstone's services enters the shop, he or she has to wear one of Issa's snakes as a pre-emptive measure. After the seraphim burn all of Brimstone's doorways to the world, Karou assumes that Issa is dead. Akiva confirms this after her memories return from breaking the wishbone.
Days of Blood & Starlight
Issa reappears to help Karou as per Brimstone's request. Akiva finds a thurible containing her soul in the Kirin Caves and brings it to Karou after discovering that she is alive and the new resurrectionist for the Chimaera. Karou recognizes the soul and is quick to give Issa a new body so that the Naja can replace Thiago's servant Ten as Karou's assistant.
Dreams of Gods & Monsters
Issa is Brimstone's assistant.
Issa is Karou's guardian, and loves Karou like she is her own child. She acts motherly towards her and is quick to reassure her whenever Karou begins to doubt herself.
- “You dreamed a different way. Akiva, too. You, the pair of you, you had the capacity not to hate. The audacity to love. Do you know what a gift that is?”
“A gift?” Karou choked. “A gift like a knife in the back!” On the bed, Zuzana stirred, and Karou lowered her voice. “It was false. It was crazy. It wasn’t love. It was stupid—”
“It was brave,” countered Issa. “It was rare. It was love, and it was beautiful.”
- In the original document written by Laini Taylor that would become Daughter of Smoke & Bone, Issa does not appear. Instead, her role is filled by a character named Haruspex.
- Days of Blood & Starlight Chapter 58, pg. 334