Bookworm

This thumb-length grub is the quiet terror of libraries and scholars. Drawn to paper of every kind, it gnaws through scrolls, maps, ledgers, and spellbooks at remarkable speed, smelling out the largest hoard of parchment from across a room. Normally dull grey, it shifts colour to match whatever it rests upon, making it nearly invisible until faint munching gives it away. It cannot harm living flesh and bolts the instant it is touched. A single grub carried home in a pack can quietly ruin a scribe's life work. For survivalists it is less a foe than a hazard to stored records, and a prized alchemical ingredient: the dark, ink-steeped residue in its body can ward written magic.