I was a foreign exchange student in Japan, and my host family would cook dinner, then neatly put the leftovers up on the counter. We ate them for breakfast. Obviously not sashimi or sushi, but things like rolled omelet and fried fish from the night before. We never got sick. They had a dorm sized fridge, so most foods were bought the day they ate them, or served as leftovers the next morning without refrigerating.
Too funny, my husband was specifically referencing some sort of Japanese meat that is aged two months (??could that be right??) and safely eaten, as a reason why we should eat this dinner