The return of the Shadowless Assassin had sent ripples across the universe, especially through the Demon Universe. She was from their side of the universe, after all.
However, what she represented now, or had represented, didn't align with their beliefs back then, and it still doesn't. She sided with the Paragon, and the demons hated the Paragon.
This hatred stemmed from an event that happened during the Blood Era.
After Asura found out that the person who spiked the drink that led to him unknowingly sleeping with the Seven Chaste Maidens was from the Demon Empire, he became so enraged that he started a bloodbath.
He killed so many that the Heavens Court, which had already started looking for a reason to cement their claims that the Asura Race was an enemy of the universe, took advantage of his carnage and weaponized it.
