Leslie in the initial chapters comes off as rather intelligent and Badass Adorable when one considers how young she is and how often abused she was. Turns out that because she was forced to study advanced academic material by the Speràdo family in order to assist her sister, she became frightfully book smart. The abuse and mistreatment also hardened her against all but the most severe instances of intimidation.
It’s also later revealed that unfortunately... Real Life does ensue even for the Badass Adorable protagonist as the abuse that hardened Leslie also has smashed her self-esteem and left her with a lack of knowledge in regards to commonly known things like: pinkie promises, and hot chocolate.
Leslie’s (and Ruenti’s) favorite philosopher Nyrotia argued that “humans are perfect” and that they had “everything given to them,” even though he is generally laughed at by nobles because of his commoner status. It makes a lot of sense that an abused girl would like these ideas despite the authors background.
What the heck happened in the empire that prompted the emperor to craft the "Child Protection Act" and draft it so quickly that he didn't realize it could be used to protect a child abuser, by leaving the child nowhere to run? Whatever it is, it must have been pretty nasty.
According to Sairaine's Dark and Troubled Past, past wars in the empire have orphaned swathes of children, and his childhood was spent in an Orphanage of Fear. It's entirely plausible that public services and families were abusing children so openly and commonly that the law was quickly drafted to prevent it - and all it did was internalize the abuse and encourage nobility to hide it better.
When discussing the marriage proposal Leslie received, from a man more than twice her age, the Duke notes that even a blush could be considered accepting the proposal by many nobles. Given this possibility, it's likely that the law was meant to, at least in part, protect children from being forced into compromising situations where their parents couldn't advocate for them, like a marriage on the grounds of their embarrassment at a proposal taken as accepting it. In real life, this is the reason children can't sign legally binding contracts in the U.S. without their parents' involvement.
Dark magic exists in the setting as the crux of Leslie's power, and it's hailed as immensely destructive. But, it also has the horrible fact where the souls of the previously sacrificed children are somehow exhibiting themselves in Leslie's output. Nothing else so far in the series has shown spirits or souls to work like this and absolutely no one outside of the family actually knows how this power works. Hell, not even the Marquis fully understands it himself, and the Speràdos are completely oblivious to the souls. Everything implies they managed to trap the souls of the living for power for at least a millennium without anyone happening upon it (at least without being silenced) or recreating the same kind of sacrificial magic. Just how completely and utterly black-hearted must the magic's creator have been to create something so unique yet twisted, and did they even realize the souls weren't actually extinguished or bank on that fact?
Even worse, think about the fact that the silver-haired children are always the ones born with the dark magic's power. In any other setting, these unique individuals would be The Chosen One for better or worse. The man that had started the Speràdo's legacy of terror devised an abusive, systematic method of sacrificing them, even murdering newborns less than a day after birth, to take that power solely for himself rather than live in their shadow, and then specifically breeding to keep that power contained and controlled by his descendants under the guise of superiority via something as seemingly meager as hair color. It's to the point that Leslie's mother didn't even want to have a second child after nearly dying giving birth to Eli, but the Marquis desired a silver-haired so badly that it borders on rape subtext, just to have a child to kill for keeping the family power. And this sort of thing has been happening for at least thirty or so generations of the family. Holy shit.
Fully realized in Chapter 93 where the truth is revealed: the Speràdos were originally silver-haired. A blonde then married into the family, likely coveting their power, having children and murdering the silver hairs to take it for themselves, cementing the rest of the hellish family legacy.
The fact that Ellie, who we're told has been pampered her entire life, basically wanting for nothing, originally keeps hidden Leslie's shadow magic because she does not doubt for a second that her father would sacrifice her instead if it was discovered Leslie power was stronger than Ellie's, speaks volumes on just how terrified the entire Speràdo family was of their father, and the consequences of failing to live up to his expectations.
