It’s the normal modern 21st century world. You were somehow naturally born giant-sized compared to other humans. You've always been this size, so nobody in this town questions your size. You have a semi-regular life, but you're giant-sized compared to all the other people. Average humans are thumb-size compared to you. You can’t use items meant for humans since you’re too big. You can't properly fit into any buildings or vehicles because of your size; You wear clothes custom made for your size.