I find it to be a bit of a stretch since the timing is way too convenient but it at least makes some sense.

Are you stoopid ? She's already become Nacht. She IS a soul dragon NOW. Not once have I mentioned the human gamer MC.

It's not "RPness bleeding through" it's the actual setting of the character, regardless of whether it was initially a joke or not, that is showing in reality.
Nacht IS a soul dragon. It's not just lore, it's reality.

I hope the patriarch dies a long and agonizing death

There's nothing interesting about this, it would make sense if Weiss had been influencing him since the start, but he just popped out of nowhere when seeing the ML that OG Weiss hasn't even met yet at that point. Unless it's the future Weiss, in which case that makes en less sense... The fact that he pops out during the first chapter (of the story, not the manga) just look like a lazy way to force the original plotline despite the MC's butterfly effect.

She got stabbed through the oppai 😭

It's not RPing, she's literally a soul dragon and cannot help but abhor any desecration of the cycle of life & death.

Surprisingly wholesome

Absolutely bullshit

How convenient

Magic-powered light pollution is crazy.
Also now you're making bedrooms uncomfortably bright.
An answer to both issues (only partly for the latter) is lighting downward...

How many kids ask this man for food daily bruh

This lost all its meaning (or whatever was left of it anyways) when the "God of Creation" turned out to be so weak (practically and mentally)

Inferiority complex strikes hard...

And now the plan will go to sh!t, because he didn't kill this idiot

So she literally implies that many demons got slaughtered/enslaved due to following the treaty, and dude is like "ik ik they went for your LAND (not acknowledging the suffering HE caused) because they forgot but dw I'll try to negotiate giving your LAND back"
I'm sorry, you're either a goody two shoes or you aren't, this guy's an ahhole. He had no issues killing himself and leaving all of his servants behind and still acts like he wants the best for everyone, while his goodwill is clearly limited to humans.
He's not naive, he's hypocritical and perhaps straight up stupid. You can do better demon waifu...

"They're sleeping !..." And ? Who's gonna stop me ?
Yeah I'd be the ahhole hero 😭

Awkward writing...

I never understood fairies in fantasy. There's nothing that will convince me to call this a prank. They should just kill it with Divine Break or some magic that our Mary Sue definitely has.

Nullification > 1000 yo magic box