Kai-Yusav Naihara

...Just accept two leaders in a group, it will not be a hassle for us.

Kai-Yusav Naihara (alternately, Kai'zav) is an Alxerion encountering in the Alphalace. She is level 495.

Kai-Yusav was originally created by the Supreme General to govern Varieleis although he managed to seal her in a capsule in a locked room to empower her up in which he say that he wanted her to be sharp as a knife when she strikes. Yet curiosities among wandering Encivils strive about the room, according to them, it was being engulfed by a "repulsive aura". Until Alicia II (Leaviel Zeryon) became an Alxerion as a head of the subclan, Kai-Yusav's capsule was broken by the shockwave she casted, implying that she got the fullest power possible. She had left the room by herself.

In Alxerian Tales
She is also known by the Alxerions as "The Sealed Princess" due to the fact that she is the creation of the leader (a Supreme General is somewhat equivalent to a king, and even the word Kzhralqaz also means 'king'). She also uses a weaker version of Versatility Staff (the signature weapon of Zaern).

Chapter 10: The Newborn Hope

See: The Twin Spectra

In Chapter 12 part 2, if you take her one of her lines in other sense, she is stalking Zaern and commonly, is aware of him, making her the possible rival of Le'aviel.

''Le'aviel: I can feel my lover's spirit... He's just here outside this room.''

''Kai-Yusav: But as far as I know, Zaern is fine, as I saw him yesterday on a skirmish with my master and his two siblings. How come your lover's spirit was here?''

In Chapter 17, by sacrifice, ahe saved the life of the infusion of the three Astars (what appears to be a weaker Dhimeirann) when he was about to be killed by a giant fireball casted by Raveira (The Astral Ace). This led to Raveira surrendering to them and being turned into an Alxerion as Ar-zari Velzayor.

The Twin Spectra
Krizeren and El-Ayara Gi-Ezars, known as 'The Twin Spectra' for their appearance as they were cohesive to each other. In Alxerian Tales, some scripts may include both speaking, named as 'I-via'

Krizeren Gi-Ezar, color assigned as black, known for the nickname as 'Yvia', is one of the encivil creations by Kai-Yusav. She is known to be closer with Azure. She has a straight hair as its hint, striped jacket, and a long skirt, footwear (all of mentioned things are black, including the eye color).

El-ayara, the white ones, also known as 'Ivy', also one of the two encivil creations. Known to be close with Mark; Appearance: (all attributes in white) eyes, jacket, hair (wavy), long skirt, footwear.