Haruo Koga (古賀 春生, Koga Haruo) is a 17-year old boy that lived with his mother near the Mutoh family. He was an ace in the track and field.
Haruo is a young Japanese boy with messy, medium length black hair, glasses, slate blue long sleeves, and khaki pants.
After the first devastating earthquake, Haruo goes to the shrine on the hill, where Koichiro illuminates to draw his family to a nearby shrine, along with anyone else who came by. He shuts himself in, sitting by a tree and listening to music with his headphones.
Koga follows the group throughout the disaster, until they get a memory card with important data on it from Onodera's base, swept down to a platform where it gets stuck. Koga decides to use his running skills to get the card, and run back within 10 seconds. Unfortunately, he gets swept away by the waves before he could make it back to safety, after throwing the cartridge to Ayumu.