Pechin is a word that can mean different things depending on the context, but often it is used to describe someone who is being very careful with their money.
Imagine you have a piggy bank where you put all your money in. You are saving up for something special like a toy or maybe a trip with your family. Each time you get some money, you put it in the piggy bank and you don't take any money out until you have enough for what you want to buy. If you are a pechin person, you might be even more careful and save some extra money just in case something unexpected comes up.
Being pechin can be a good thing because it helps you reach your goals and avoid spending money on things you don't really need. But sometimes, it can also make it hard to have fun or take risks because you are so focused on saving and being careful.
Overall, being pechin is about being smart with your money and making sure you use it wisely.