Ryraryus Spenia Ai Indarun

Ryraryus Spenia Ai Indarun (リュラリュース・スペニア・アイ・インダルン) is a naga who rules western Tob Forest.

Appearance
Ryraryus is a naga with the upper body of an old man.

Personality
Ryraryus is probably the most intelligent of the Three Monsters. Unlike Guu, Ryraryus's nature is quite discreet. He anticipated the huge power of the Ruler of the Building of Ruin and decided to ally with Guu against a common enemy. The naga mostly speaks in third person.

Background
For a substantial long time, he ruled the western Tob forest and was part of the status quo that kept all monster activity within it in check for countless years.

The Two Leaders Arc
Ainz Ooal Gown appears before the two leaders of the forest. Though Guu arrogantly shows himself before the Overlord, Ryraryus takes caution and uses his magic to turn invisible.

After negotiations had failed, he witnesses Ainz's power as he annihilates Guu and his followers. At first believing he is safe from harm, he tries to use his invincibility ability to hide himself but soon finds out that is untrue as his weak cloaking magic was seen through by Ainz and Aura. Captured and restrained by Aura, she prepares to kill him, but is stopped by Ainz.

Ryrayus pleads for his life, offering to be his servant. His pleads for mercy were accepted and the naga is given control over Guu's territory.

Abilities and Powers
Owning similar strength to Hamsuke, it seems that Ryraryus is also around level 30. Though his physical ability seems to be inferior to Guu, he can use some magic including invisibility. He can also sense the general emotions of a target. It is not clear whether this ability is a Special Talent of him or the racial trait of the Naga.

Guu
Guu was Ryraryus's rival, however, the naga agreed to join forces with the troll so as to stand against Nazarick.

Ainz Ooal Gown
As Ryraryus was the only member of Guu's party not to insult his name, Ainz Ooal Gown decided to spare the naga. Upon seeing the undead's terrifying power, he swears his allegiance to the Overlord.

Aura Bella Fiora
Ryraryus had remembered that the dark elves were the original rulers of the Tob Forest, and attempted to caution Guu from fighting.

Trivia

 * If it wasn't for Ryraryus's meddling, Guu claimed that he would have invaded the ruins in the forest long ago.