The first time it happens, Ginko puts it down to simple distraction.
He's watching a small group of Luminous Tears dance gleefully in the drizzle that's lazily falling from the sky, despite the rapidly falling dusk (they should have escaped a long time ago, to join fireflies and hide from the oncoming darkness) all the while he's keeping the other eye on his notes, to make sure that they are at the very least barely legible. So when he puts his pencil down for a moment, but cannot find it anywhere logic dictates it should be afterwards, he shrugs his shoulders and procures another one from the depths of his many drawers.
The second time his pencil disappears, Ginko once again suspects nothing. The kids from the village he's passing through are infinitely fascinated by his person and take up most of his focus. They clamour around him like a flock of ducklings and ask so many questions, that Ginko has barely any time to breath. As he's chattering away, he roughly sketches out some of the mushi he's describing, and the kids collect them like treasure. A pencil pilfered in all this clamour is not even surprising. He just takes out another one.
The third and fourth times it happens, similarly, prompt no reaction from the man.
However, when his pencil disappears for the fifth time, Ginko's brows travel high up his forehead. Distraction as an excuse can take him so far, but the pencil disappearing almost right out of his hand is proof enough that something is going on. Ginko looks around, patting the grass he's sitting on more for the sake of doing so than hoping he'll find anything. And, predictably, he sees nothing out of the ordinary.
He checks above to make sure (still nothing) and exhales. The last thing to do is to carry out a simple experiment.
Ginko reaches for another pencil and finishes the letter he hoped to send out soon but , before setting the writing utensil down, he takes a long drag out of his cigarette. The smoke fills his lungs, swirling there lazily and waiting to be let out for a hunt. Ginko keeps it in, and finally puts the pencil down, next to his knee, keeping it in his peripheral to not spook the little thief.
This time being prepared for the pencil's disappearance, he notices wispy, almost translucent, mousy fingers carefully reaching for it. When the smoky paw closes on the wood it moves back almost immediately. Ginko barely has time to exhale a plume of smoke, before the hand disappears. Caught, the mushi instantly opens its fingers, letting go of the pencil and starts to wriggle frantically, trying to flee.
Upon closer inspection, Ginko can see that the hazy little hand has its origin at the bottom of his box backpack and he snorts a silent laugh, amused that the mushi chose such an oblivious spot as its hiding spot. The smoke is slowly dissipating so Ginko raises the box to see where exactly the Nithing Paw took residence. After a short examination, just as the mushi finally wriggled free and swooped back to its little den, Ginko notices a tiny crack in the board supporting the bottom.
"What a nifty little thing" he chuckles. The gap is so small, that Ginko would probably not notice it for a long time were it not for the new tenant.
This type of mushi are common and generally harmless, but having them pilfer things can get tiring very quickly . Besides, Ginko would rather avoid a situation where the critter steals something he needs to deal with another mushi. He gently sets the box backpack down and searches it for herbs that should smoke it out after burning.
The forest surrounding them was brimming with little nooks and crannies that the Nithing Paw could use as a new home, so Ginko had no remorse for evicting the little pest.
After collecting the herbs and arranging them on an old ceramic saucer, Ginko wanders off and searches the area for a few thick branches or bigger rocks, on which he can prop his box backpack. When everything is set and ready, he begins the process of smoking out the unplanned tenant.
Ginko lits the herbs, gently blows on them until they start to smoulder, and carefully slides the saucer under the box. It doesn't take long before the first missing pencils clatter out of the crack, and then, against all logic and physical limitations, a few other trinkets fall out. The Nithing Paw had to snatch them from people who unfortunately found themselves near Ginko.
Glass marbles, scraps of paper, a hairpin, needles, and even prayer beads fall out one by one until the bottom of the backpack is almost empty. Ginko leans down and gently blows on the smoking herbs to increase the heat, and waits for the mushi to escape the now stinky den. After a few moments, delicate finders peek out, a pair of shiny eyes above a snout flashing in the hole's darkness, and in the blink of an eye, the mushi jumps out of its hiding and scampers away from the smoke.
Ginko follows the escape with his eyes, and after making sure that the Nithing Paw tucks itself into one of the nearby trees, he takes the box backpack off the makeshift smoker. For a moment, he debates with himself what to do with the filched trinkets, but in all honesty, there is nothing much he can do besides making use of them later on. Selling or giving them away is the best option. Ginko puts them away wherever the space in his drawers allows, buries the ashes in the ground and slings his box backpack over his back, setting off forward to put some distance between himself and the Nithing Paw just in case the little mushi may still be tempted to move back into the box's bottom.