This little leather bag has a short piece of string sewed to it that holds it closed. Upon inspection, using identify reveals it to be magical and how it works. Once you stain the string with a drop of blood, the whole string turns into the color of the blood, you become the owner and the bag begins to work as it is supposed to do.
Although never weighing more than 1 pound, this bag can hold as much coins you place in it, but nothing else than coins or other accepted currency. Whenever the owner wants to take money from it, they can think of the exact amount and it will be given in the way they want if the money inside the bag is enough (All in gold coins, the minimum amount of coins possible, an exact quantity of each coin...).
If some other thing is placed inside, the bag will spit it, and the player has to roll a d6. If the result is 5 or 6, all the money inside will be spit too, in the form of gold coins, and won't be able to be used again for 1d4+2 hours. Also, if the bag is pierced, the same effect will be applied, but the bag will be unusable until mending is applied on it or a magic crafter fixes it by magical means.
Only the person that has stained the bag can use it, and if someone else tried to open it, only a few gold coins will be shown (If there's enough money on the bag to be displayed). If that money is taken, it actually disappears from the bag, and it won't display any more money until the owner uses it again. If someone forces the owner to open the bag (such as moving their hands to do so) the same effect will as if it wasn't the owner. This means that only the owner willingly can draw money.
The only way to change the owner is if the owner tells the bag so. When this happens, the bag will spit the money in gold coins, and the string will lose its color until it is stained again. If the owner dies, the same effect applies.
Placing a bag of the merchant inside an extradimensional space created by a handy haversack, portable hole, or similar item instantly destroys both items and opens a gate to the Astral Plane. The gate originates where the one item was placed inside the other. Any creature within 10 feet of the gate is sucked through it to a random location on the Astral Plane. The gate then closes. The gate is one-way only and can't be reopened.
Notes: Creation, Summoning, Social, Utility, Deception, Container, Outerwear