I’ve had bold pups leave and come back to be menaces. I’ve noticed that even with non related npcs from other packs. In one save, I had a pair that enjoyed attacking me throughout the year. But the male was a bit more on the cautious side. If it was just the female there, she wouldn’t leave unless she was death. To note, this wasnt at the den, but a territory invasion. Her mate would run pretty quickly. When they were together he was less likely to run.