Grocery store opened 24 hours. They have lunch box food like at the convenience stores except a little cheaper. A good variety of Japanese candy and snacks like Kitkats, Pocky and Calbee chips.
Cheap food, has everything that you want and cheaper than a normal convenience store in Japan. Staff usually can't speak English though, but you'll still be able to manage. It's only hard to determine what the food is made of when there's no image and just Kanjis, haha