While the Central Continent leaders were discussing issues with the giants, Cain got bad news from the Southern Continent. Someone was building up an army to try to take over the furthest inland areas of the continent.
They had already received two reports of Guardians being assassinated right before a city was attacked by unknown forces. Then, the morning after the attack a Demon named Morgeth had come into town announcing that he was the new Guardian and that the entire city had been drafted into the army of his alliance.
How many cities it currently occupied, Cain and Cyrene did not know because the trade routes had mostly closed so the news wasn't spreading like usual.
They were still a ways from the group allied with Cain, but they had been expanding in his direction, which would naturally lead to conflict with this Demon Alliance.