Cosmos Queen Beast
After some back and forth, it turned out that Fenrir, Jormungandr, and Hel had forgotten a simple fact. They had known that by using their Divinities through Michael and their bound Soultrait Symbols, they created seedlings of their Divinities inside Michael. But they forgot that the Primal would hunt him for possessing the same Divinities as the siblings. The reason they'd been hunted and sealed was because the Primal hadn't been strong enough to kill them. The siblings had to be sealed away once found.
But what would happen if someone with three Divinities like that were to appear? The Primal would gather and kill Michael with combined efforts before it was too late. While that might be bad, it had always been known how hard it was to find the Primal. Usually, the Primal would come and find you. After all, they could seal their powers perfectly, and it wasn't like many of them were still alive.