Baby Mimic

The baby mimic holds as much as a regular backpack. 

Toothless maw. When a creature opens the bag without patting it first, the baby mimic bites the creature. For 1d6 rounds, the baby mimic stays attached to the creature and imposes disadvantage on their attack rolls. 

Adhesive. The baby mimic can adhere to any surface on a command word. (it can be released with the same word). 

Notes: The PG must spend one afternoon with the baby mimic.