I love Japanese Konbini! They have everything you want! From food, to drinks, to umbrellas, to make up… it is always lovely at the end of the day to shop there. And the best thing is, they are found in abundance in most cities in Japan. Different company of konbini will have different products. I know that Family Mart even has a Muji counter that sells soap and moisturiser. Their bread and food is also cheap.
If you go to Japan, don't forget to drop in at their konbini (all the different companies') and explore!