He doesn't lie. So it would be bad to lie to the populace about his affair with Elaine and Incest isn't much of a deal in Alfheim when Royal families and Nobles practice it all the time to keep bloodline pure.
Which Chinese one. I am writing from scratch. It might look like it because when you read a lot of fanfics. Some ideas do get mixed in there. But I don’t remember one like this
His target is to be the strongest being and make his whole family and Harem immortal. Plus some side quests. He will struggle with some fights because Kage level is barely at the level of someone like Doflamingo from Canon. So you can estimate.