Ath'tas
Ath'tas bless you, child. You are to be our new ruler. All you have to do is feed your sibling to him and he will grant you much power.
Ath'tas, God of the Abyss. He is the god that the city surrounding the Coronation Pit worships. When well fed, he is benevolent and capable of mercy. When not well fed, he brings upon the end of the city with him. He is said to have once been mortal, and a prince of this city. That was a long time ago now, many have forgotten the true story of this god.
Luckily, I do know the story, it's one I've been told many times in my homeland. I would tell the populace about the god they worship being a demon that they constantly feed, but I would be branded a heretic and might not be allowed back into this city and I feel like there are things I haven't figured out yet, like that monolith.
Love the drawing ^^