The son of Gyuuma Ou (King Gyuuma) and a female demon who has been trapped inside a stone wall. Although he is a nemesis for Sanzo and the others, Kougaiji is really not a bad person. He is a true friend to his followers, Yaone and Dokugakuji, and especially attached to his little sister, Ririn. He is blinded and confused, though, by his determination to bring his mother back to life. Following a battle with Goku, Kougaiji was badly wounded and nursed back to life by Ni Jieni. Unfortunately, Ni Jieni did much more to Kougaiji than merely cure him... and now he acts as if brain-washed, becoming a cold and lethal follower of Gyokumen.

A kind, polite young woman. She is deeply in love with Kougaiji and has been entrusted by him to take care of Ririn. Because of her sweet personality and polite demeanor she has developed a certain respect for Hakkai, with whom she battled in volume 2. This character is so nice, actually, that we've had to concede that the only reason she remains in Gyokumen's service is that she deeply loves Kougaiji and is willing to do anything for him. In this respect she is almost pitiful, dedicated to a cause she doesn't truly believe in because of her devotion and love for one man.

Kougaiji's loyal follower and best friend. Dokugakuji is a large, good humoured man who, like Kougaiji and Yaone, is not truly evil, but blindly devoted to the man he chose to follow. Dokugakuji is really Sha Jien, Gojyo's older brother. Ten years ago he killed his mother in order to protect Gojyo. Although he still lives with guilt he often thinks of Kougaiji (whom he calls "Kou") as the man who returned meaning to his life, and this is why he is so loyal to him, even after Ni Jieni warps Kougaiji's personality.

 
Kougaiji's feisty little half-sister, who speaks in a strange dialect in which she refers to herself as oira instead of atashi or even boku. Because she is very young and increadibly spunky the grown-ups don't often take her very seriously, and her battles soon degenerate into farce. However, she is fiercely and touchingly loyal to her older brother, even if she doesn't fully understand why he is so attached to his petrified mother and working for Gyokumen, who is Ririn's mother.

 
A sensual, cold and calculating woman. Gyokumen Koujyu (Empress Gyokumen) is determined to revive the legendary demon Gyuuma Ou and has enlisted researchers and Kougaiji and his followers in order to help her achieve this goal. She is a domineering woman that likes to treat those who serve her as instruments for her personal, sadistic pleasure. She has no real love for anyone, even using her own daughter and her half-brother as part of her experiments. As a good villain, though, she is shrouded in mystery and half-truths, and only the story itself will bear witness to whether she will be a true force to reckon with or not.

A severely twisted researcher in Gyokumen's team, Ni Jieni is in all probabilities quite insane. He has a stuffed toy fetish, and is usually never without stuffed rabbits. A mocking, condescending man, he calls Kougaiji "Prince" and delights in tormenting him and his followers. Like Hakkai, Ni Jieni hides behind a perpetual smile, but his loyalties are questionable. While he seems dedicated to Gyokumen's efforst in reviving Gyuuma Ou, he also seems to harbour his own personal agenda, acting as a make-shift Judge of the World.

A quiet, dedicated researcher. She dislikes the chauvanistic Ni Jieni intensely but is aware that she is not permitted to leave her position. Like Yaone, we have to wonder why this woman chooses to work for Gyokumen, whom she seems to neither like nor respect. She never speaks about herself or her motives, merely carries out her duties with professional efficiency. Because she is so reserved Ni Jieni asks her: "For whose sake are you living?" She gives him no reply and so remains a mystery.