On the Forgotten River, he made a contract with him.
Each gets what they need.
He returned to the world and collected all "sources" just to complete the forbidden object that was not allowed to appear in the world.
He stayed in the River of Forgetfulness and created an "immortal banquet" just to draw out the lonely soul hiding in the netherworld.
What you want.
What I buried.
At this moment, everything begins.
──"The Ghost Story of a Hundred Nights"