After making a full round on the edge of the forest, Blake had finally learned quite a few things about the humanoid demons' base. And some of that information was the one that he and Robus needed for their plan to get as many souls as possible.
Blake had found out that despite the humanoid demons in the base all flocked together and there was almost no chance for him to be able to sneak in and kill a few of them without getting caught, there were still ways for him to get the souls.
They indeed grouped up together when they were still inside the base or on the shore where literally hundreds of them were working side by side.
But when it comes to hunting for food, chopping wood, or gathering other materials in the local areas, the humanoid demons worked in smaller groups that weren't impossible for Blake to deal with in a quick manner.
However, even after knowing these, Blake didn't go back to Robus right away as there was still something that he wanted to test out first.