Even evil has standards I guess? Granted, this is the King we're talking about, but still incest is pretty extreme for me, especially if they are not consensual.
As you said, it's extreme for you*. That in and of itself is weird. What he has done to those other boys, is it any less horrifying just because he didn't father them? I personally don't think so, but it seems like there are people who do.
Also, for someone who does such grotesque things, do you really think it matters if a DNA sequence of a pretty little victim is based on his own? I'd say it has more to do with the gold in their hair and eyes then with them being his spawn.
I actually thought the same. Predators are always drawn to easy prey, and Dandy's as easy as they come, due to his naivete and his ignorance of the king's moral depravity. So it's weird that the king doesn't spare a glance at him at all. Maybe it IS beacuse of the golden magic in Dandy's blood, but... The other thing is that Dandy's eyes are not golden, so the gold running through his veins or wtv is not as potent as the gold in the king's other children. But idk.
It's all a matter of preferences really. He beds children around Dandy's age, but didn't even spare him a glance. It's clear that he didn't see him that way. Like you said, it would be too easy to pull Dandy to his side, but he simply didn't. Just because he's a villain doesn't mean that he has to commit every single sin in the book.
That king, it's weird that he doesn't practice incest, because he's trying real hard to rp it. Calling those who belong to his harem his children, yet staying away from his own actual children. And the way he thinks of them....it's so oddly separate. He likes them cute and young and male, and honestly, Dandy was kind of a perfect specimen of the king's ideal, yet he didn't even spare him a glance. Fact is, Dandy idolized the king, which is something the pedo clearly wants, it wouldn't even have been hard to include his other sons in the harem, brainwash them into blind worship, yet he just let's them roam and gorge themselves on golden roaches. There was someone in the comments, startled by the possibility of the king being attracted to his own son, but I'm more weirded out by the fact that he wasn't. He's warped, twisted, insane, it's weird that he's actually keeping away just because he's the actual father. Then, there's the awful fact that he's harming them so brutally, yet there was that page, when the poisoning was happening, in which he is shown surrounded by boys, as if their mere presence is healing him, and the way he looked at them, as if they were made of glass and flowers and feathers, so easily broken, so easily crushed, so so precious. The fact that he's a rapist was obvious from the beginning, but he uses his little dolls for more disturbing things too.
Maybe sparing them of his perversion has something to do with their gold filled veins?
Another thing, he's got quite a few sons, and not a single daughter. What's up with that?