At some point after Thaegan was given control over Ruby territory, Jin and Jod set up a home in a small valley. Their home was on a section of land surrounded by a ring of quicksand. They placed a bell on a broken of a warning sign - the remaining part reads "Ring and Enter" - near the entrance to the valley to lure in unsuspecting passers-by who would fall into the quicksand trying to enter the area. Jin and Jod would then "rescue" and drug them before killing and eating their captives. The only safe way to escape the ring was by using a series of hidden stepping stones. The stones were hidden halfway under the quicksand and surrounded by leaves with meaningless, red symbols scrawled on them, another trick meant to fool their captives into falling back into the quicksand.
One of their many victims was Manus, a Ralad that Jin and Jod found too small to make a good meal. Instead, they kept him as a sort of pet until he managed to escape by using Jin and Jod's own stepping stones.
Jin and Jod, along with their mother and siblings, are mentioned in The Enigmatic Giant's final riddle to Lief. They first appear physically when Lief, Barda, and Jasmine stumble onto their home while travelling through the Ralad territory. Lief had found the sign while searching for firewood and called his friends over, only for the three of them to fall into the quicksand. Jin and Jod saved the trio and Jin introduced them as "Nij" and "Doj", respectively. The siblings take Lief and his companions into their home and Jin goes off to prepare the meal while Jod gives them drugged drinks.
However, Lief inadvertently touches the Topaz on the Belt of Deltora as Jod hands him more food, which clears his mind and allows him to see through their illusions. He guesses their true identities by remembering the Giant's rhyme and alerts Barda and Jasmine. The group manages to sneak out of the house when Jin and Jod hear their bell ring again and rush out, excited at the prospect of a feast. The intruder turns out to be Manus, who tossed a large rock into the
quicksand to distract them before racing into the house to try and free Lief, Barda, and Jasmine. Jin and Jod catch up to him and chase him back out of the house, furious at the sight of their former slave. Jod manages to catch Manus with his hook, but Lief cuts it in two with his sword, and Manus manages to wordlessly tell Lief how to cross the stepping stones. Lief, Barda, and Manus make it across, but Jasmine is struck in the shoulder by Jin's axe, knocking her into the quicksand. Lief and Barda manage to free her when Kree arrives and distracts the duo, though his wing is broken in the process. Jin and Jod leap after them, only to sink into the quicksand, much to their surprise and horror. After they sink to their doom, Jasmine reveals that she had moved the leaves, knowing that Jin and Jod would be too angry to notice that the pattern had changed.
They and their deaths are briefly mentioned again by Thaegan as part of her motivation for attacking Lief, Barda, Jasmine, and Manus at the Lake of Tears.
Jod's role in the anime was the same as in the book. However, after his death, he and Jin returned as spirits accompanying their mother and siblings. He followed Thaegan into the afterlife when she committed suicide.
Also, in the anime, Jod gained the power to merge with Jin to become a large two headed version of themselves.
Jod is described as being a bulky, ogre-like creature with mottled skin covered in sores and lumps. His eyes are reptilian, flat, and yellow and his mouth is full of crooked, very long metal spikes for teeth, and his nose is simply two flaring nostrils. His tongue is fat and blue and his lips are swolen. His nose resembles a pig's snout more than a normal nose, being only two flared holes. When disguised by magic, Jod takes the form of an overweight, elderly man. He is balding with a fringe of grey hair around his head, has a large, bushy mustache, has pale blue eyes, and was described as looking cheerful and comforting by Lief.In the anime, Jod's human form is changed significantly. He is much smaller and more elf-like in appearance. His skin is peach-coloured, his mustache is replaced with a white beard, and he sports a small shock of white hair on the top of his head. He wears a grey shirt with a faded green strip of clothing wrapped around his neck and shoulders.
Jod and his sister act in a much more sadistic and intelligent manner when compared to their other siblings. Rather than actively hunting, the pair set up an elaborate magical trap to catch prey with relative ease. They speak very excitedly and openly to each other while luling their captives into a false sense of security, often smiling pleasantly while saying atrocious things, knowing that their language is normally disguised by magic. Upon realising that Manus was too small to be a satisfying meal, Jin and Jod opted to keep him as a slave or pet rather than simply kill him. Jod also brutally beats Kree with the remains of his hook.
Jin and Jod were capable of using magic to disguise their speech as a foreign language. In actuality, it was normal speech, but reversed, so that phrases like "Soon you can sleep forever" become "Reverof peels nac uoy noos". They are also capable of disguising themselves as a sweet, kindly, human couple, and their home—a dark, disgusting cell—as a lovely, warm home. Jin and Jod are seemingly quite skilled in deception, smiling pleasantly in their human forms and acting surprised by their "warning sign" being broken.
Jod appears to be the more physically strong of the two, as he is the one who holds the hook to pull in captives, though Jin is still quite strong on her own.
Jod and his sister use a massive, hooked pole to reel in their intended prey from the quicksand ring. Lief slices this pole in two when Jod attempts to use it to catch Manus, but Jod continues to use the remains of the pole as a weapon. The pole is presumably lost with Jod when he falls into the quicksand.