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 the Western Tob Forest. He is currently an immigration official for the Sorcerer Kingdom.

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
In Tob Forest, Ainz Ooal Gown appears before the two leaders of the forest. Though Guu arrogantly shows himself before Ainz, Ryraryus takes caution and uses his magic to turn invisible.

After negotiations had failed, he witnesses Ainz's power first hand as he annihilated Guu and his followers. Believing he is safe from harm, he tries to use his invisibility ability to hide himself from being seen by him. Unfortunately, he soon realizes his weak cloaking magic is incapable of fooling the likes of Ainz and Aura. He got captured and restrained by Aura, she prepares to kill him until she was stopped by Ainz.

Ryrayus pleads for his life, offering to be his servant. His pleas for mercy are accepted and the naga was given the order to attack Carne Village with his minions.

The Paladin of the Holy Kingdom Arc
Ryraryus later reappears as a spokesperson and immigration official in E-Rantel. He greeted the delegation from the Holy Kingdom and helped them familiarize themselves with the Sorcerer Kingdom.

Abilities and Powers
Owning strength on par with 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 his 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 them.

Trivia

 * He refers to himself as "This old one".
 * If it wasn't for Ryraryus's meddling, Guu claimed that he would have invaded the ruins in the forest long ago.
 * He stopped eating humans after Ainz made a declaration it is forbidden to do so.

Quotes

 * (To Ainz): "This old one has a long name too. This old one is the Serpent of the West you spoke of — Ryraryus Spenia Ai Indarun. Oh, invader Ainz Ooal Gown. This old one thinks their brains are not matched with their bodies, but there are pros and cons to them ruling over this forest."
 * (To Guu) "Guu! This fellow, Ainz Ooal Gown is too unnatural! We have to work together to defeat."
 * (To Ainz): "This old one is happy to serve under your rule! The weak submitting to the strong is only natural. This old one will brave hell for you with no hesitation!"
 * (To Ainz): "How, how frightening. My lord, you must think that it’s fine whatever happens to this old one. My lord must regard this old one who rules the western forest on the same level as rolling stones."
 * (To the Holy Kingdom's envoys about Ainz and his servants): "He is ten times more powerful than you can imagine. Him aside, even his subordinates are extraordinarily potent...frankly speaking, there is no safer city than one which His Majesty defends."
 * (To the Holy Kingdom's envoys about Guu): "This one does not know why you have come here. However, let me give you some sage advice, that an old friend -- a certain late contemporary of mine -- learned with his own body. Declaring your opposition to His Majesty would be foolish in the extreme. You would be best served by promptly genuflecting before him and begging for his mercy."