make myself useful

How does she protect herself? Simple; she really didn't. Eden pondered how to explain that before she had an idea to explain the shell more than herself. That would be a difficult explanation. "A shell, any of these shells" she raised a paw to gesture "they are not 'alive'..." Would he be able to understand that? "they do not breathe or live... They are shells for other animals. Smaller ones, that need to protect themselves."

She gave a nod to a hermit crab walking a bit away from them, trying to hurry from the wolves.

"A crab will pick a shell they like, and when they outgrow a shell they leave it. They'll pick another, bigger shell. Maybe with spikes, and maybe without spikes" Eden tried to explain "the shell itself protects the crab. It's hard and shelters them. It's like a pack. Strong and able to shelter" She gestured to the land around them, smiling "the Plunder protects me, even when I don't have a shell to make myself strong."