He followed the method in the Demon Clan's inheritance, establishing three seals in his body to seal the Monster Core from being discovered. As a result, he could only exert the power of the Fourth Great Realm on ordinary days.
As for his moves carrying demonic energy, it wasn't a problem in Antai Country at all.
Owen Bertram dispersed Alen Charle's soul, then opened his hands, quickly constructing layers of Array seals. These seals created a special space that held the Monster Core - such an Array structure had once held the Origin Object of Copper Gorge Extinction Domain, the cluster of Green and Red Energy, even if only for a short time.
Sealing the Monster Core naturally wasn't an issue.
Then, Owen Bertram swallowed the Monster Core and used the Heavenly Butterfly Change to transform himself into the appearance of Alen Charle. There wasn't any flaw in his cultivation method or energy.
After preparing everything, he said to the King of Souls, "You can put away the Abyss now."