Survival: Another Story

A Survival side story, set between the events of chapters 76 and 77.

While travelling on his journey Satoru comes across a boy drowning in a river. He attempts to save him, though is swept away by the current and loses consciousness. Upon waking he finds himself in a mysterious city ruled over by a cruel tyrant.

The chapters which make up Survival: Another Story were originally published in Shounen Sunday alongside the main series, and are included in the first 22 volume print by Shogakukan. However, later reprints have always collected the chapters into their own, separate volume.