|Japanese name:||榊原 恒一|
|Nickname:||Sakaki, Horror Teen|
Height: 167 cm
Weight: 55 kg
Kouichi Sakakibara is the new transfer student into Tomoiyama North Middle School's third year's third class. He is 15 years old and the only son in the Sakakibara family. His mother supposedly passed away 15 years ago after giving birth to him...
He has pneumothorax (collapsed lung),the reason why he is absent from the school for a month at the start of the story.This is also the reason why he doesn't know Misaki was treated as 'one who does not exist' that year.
Voiced by: Atsushi Abe