Ubiquitous throughout Japan, convenience stores have come a long way since the first customer walked into the nation's first 7-Eleven outlet more than 43 years ago and made the inaugural purchase.

What did he buy? Was it a beverage, rice ball, bento or other food item, or perhaps a magazine, underwear or some other basic necessity convenience stores typically stock nowadays? Legend has it otherwise.

At that moment during the mid-'70s, there was a heavy downpour and a customer walked into the store a little before 7 a.m.