Reaper absolutely blames himself. Because I feel like, as we know, Geno has always been kinda blunt and boundary-pushing (ex. In his childhood home w/ his mom's new flings or overworking himself in academy) but except for when he was little he kinda has the skill to 'justify' being an ass. (And none of his actions before were ever, like, romantic or sexual in nature because those weren't part of his plans to get info, so his prior stuff is more annoying and rude than like. Heart-shattering.) So when Reaper meets him Geno tests those boundaries, those boundaries become far looser because Reaper pushes back on him very little, and he subconsciously realizes that this puts him in a VERY high position of power. And Feno is passively very power hungry. (<- smth smth like when folks in poverty develop food anxiety, Geno was always pretty powerless in the grand scheme of things as a kid and getting good at his craft grants him the freedom to do/say whatever he wants, basically.) So. Yeah. Reaper without realizing it made Geno WORSE. Which is fine when he's isolated to Sanctuary's castle + Reaper's company because everyone around him is high-ranking and could do good w/ a little disrespect and boundary-pushing. Reaper, like u said, likes it because Geno is actually getting closer with him whether it's intentional or not, and Reaper doesn't want him to stop.

But when they encounter Dust? Well, Reaper assumes things are similar, in a way, to his own kingdom. Like, part of his brain knows that Dust was once a criminal, that he was pulled from trafficking work into being a Knight, that he's a *criminal*. But the other part of his brain sees that the Knights are second only to the King in Orchard. Thus he figured the power the Knights were gifted probably gave then similar ideas of class limitations to his own court. He sees the Knights as other nobles. Sees Dust as equal in status to Geno. So when Geno is pushing boundaries *in* his line of sight, he doesn't really stop him. Because surely Dust could use a refreshing break in the status quo too, right? He would object, right? (And ofc Geno has not a though in his skull beyond 'Ooh, new magic :]' with a hint of 'do I actually care about this guy now???')

But for DUST We know it's a nightmare rn. Because ultimately the power imbalance is huge (as we've discussed!!!) and Geno's borderline harassment is just never commented on by Dust because if he does, will he break the treaty? Will he drive them away? He's go no ground to stand on against a King and a Royal Mage of the country That's helping them.

And smth smth Reaper doesn't know, not until way later, that Dust's criminal background wasn't all sunshine and roses. He had to claw from the bottom to become a head of the trade. He has issues Very Specifically w/ people not respecting his boundaries thanks to that upbringing. Reaper may have had a childhood of war, but it's hard to get your soul-harassed when you literally kill everyone who tries to touch you. Didn't even occur to him that promoting someone doesn't really erase their trauma.