In Merrick's case, it was that he simply had to be alone; he's more efficient that way. When guarding their borders he could mount a quick sneak attack, unless he and Cyril planned to outwit the humans and steal from them. And of course, he preferred being by himself. It's good to get away from the judgment of other people, or the anxieties he feels when around them. Being around so many people now is going to take some serious getting used to.

"I wouldn't have come here without Cyril," he tells her while they work on the tent together. "And if course Gavin would join. He never misses an opportunity to make a fool of himself. Pel and Beleth were a surprise, though."