Tsutomu Yamaguchi was a 23-year-old businessman working for Mitsubishi in 1945. While he was in Hiroshima on a business trip, the first bomb was dropped by the USA. Luckily, Yamaguchi was far enough from the explosion to escape with minimal damage.
The next day, Tsutomu returned to his hometown. Nagasaki. You can probably see where this is going, but while he was at work, the second bomb fell. He survived this explosion relatively unscathed.
Mr Yamaguchi became an advocate against nuclear weapons and called for their abolition in 2006 at a UN conference. He lived a long life and died at the age of 93 in 2010.