Grey and Void started their journey through the secret realm. With the powerful Gnomes no longer active in the secret realm, they didn't have anything to worry about. Grey didn't even bother to head back to the castle which is the hideout of the Gnomes, there was nothing left for him there. He knew the Princes wouldn't dare to return, well, unless they brought reinforcement.
However, that would take a long time and he had to make the best of the current opportunity he had. He still had a few people he had to give treasures to.
Although Arthel was presently under his father, technically, he was the one who brought him here so he still had to be responsible for a few things relating to his training. There was also Cori who was like his little sister. She needed a good amount of treasure to make her body grow faster into her current strength so she would be able to increase her strength and fight stronger opponents.