Kai had slept as he had never slept before. He dreamt about his own home, how his biggest worry used to be whether he could spend enough time at home to watch some stupid shows. These dreams were utterly vivid and almost lucid, so he almost didn't want to wake up.
What was more interesting, however, was that Aethereom left a large book in Kai's mind's eye before turning silent as if he was never there. Kai took a break from his dreams every once in a while, and the book was very hard to understand, he couldn't make the heads or tails of it.
As the skeleton started sleeping, Kai's eyes turned purple again, almost as if finding a middle ground between the spirits.
Aethereom's residual spirit had possessed his own body back from Kai and killed a Demon Duke with impressive strength. With a black sun in the sky, most of the incubi killed in battle were raised by it and followed Kai's vessel later to protect it.