Nocturne is the demon in For Damacia

I had the same thought as I was reading it: it's never confirmed, per se, but it would make a lot of sense to be the new lore for Nocturne: after all, his current lore on Universe is basically just his old lore with all references to Summoners stripped from it.

Overall this actually fits kinda nicely with Nocturnes altered lore.

I mean when the Universe page was released,they changed nocturnes lore from him killing and hating the summoners to him killing a bunch of mages. And sure I didn't really pay much attention to this as it felt like a quick fix,to erase any mention of the IoW from his lore and i was certain that his lore would get completely changed once he receives a lore update.

But now we have a story of a demon who can literally summon nightmares out of others in a city state that is extremely afraid of magic and hunts down magic-users and with Nocturnes changed lore it actually implies that he does hate mages,which adds up quite nicely. So he might be the nightmare of a demacian mage,who fears that others might see him as an abomination and that they'll hunt him down. Heck what if it turns out that he is actually Luxs nightmare?After all you know what they say,the brightest light casts the darkest shadow