Xerces

Story
He is the second most senior of the Incubi Kings. He appears apathetic and often stays silent, but there is an aura of power around him that even the Empress respects and fears. He is often accompanied by his subordinate, Xestris.

During the Gathering, it's revealed that his kingdom is adjacent to Esthera's, but the Anak doesn't contact her outside of the Gatherings, which rubs her the wrong way, but he doesn't allow this to affect him in any sense.

He shows interest in the Empress' plans concerning Simon, but the real reasons are unknown so far. During the first Gathering, there is no opportunity to interact with him. He doesn't seem to pay much attention to the things that happen around him, but stays well informed. He doesn't intervene or participate in many of the Gathering events organized by the others.

We know from the prologue that he harvests Theoson, whatever it can be. Maybe the "Theo", greek for God, in Theoson is related to his interest in theology. It's probably a resource coming from the Tower.

Simon meets him for the first time during chapter 4 in the Tower. The Anak says that he's mainly interested in maintaining balance from a metaphysical standpoint, hence his disinterest with world affairs. He tells Simon about the Fucklord's incoming attack through the Tower, and about a hateful Entity wishing to destroy reality itself. He wishes for both to fail, but provides no reason as to why he doesn't stop them himself, despite Simon's insistence.

Later in this chapter, he meets with the Great Sage of Ghenalon. The death of the latter is then reported by Fheliel. While it's probable that he killed him, the reason is still unknown.

During the Second Gathering, the Anak takes a more proactive role, albeit still mysterious. Investigations reveal that he is responsible for the appearance of two new Incubus Kings, the Skullpounder and Nyst. The later is a Tower construct directly controlled by Xerces, and asks to be in charge of a day's events. The Anak also organizes an event, which is unusual coming from him. At the end of the Second Gathering, he abandons Xestris to fight to the death against unstable Chosen and rival Incubus Kings, but she survives and informs Simon that Xerces seeks to tweak fundamental rules of reality to increase stability.

Trivia

 * His character art was first created and posted on the Japanese blog Closet. This include his faceset, portrait, and chibi.