Ichi the Killer Manga omnibus volume 1 collects volumes 1-2 and features story and art by Hideo Yamamoto.

Ichi may seem like a spineless weakling—but when the tears start flowing, a terrifying transformation takes place. Driven to his mental breaking point, Ichi becomes an unstoppable force of carnage, unleashing a torrent of violence on his next target. When his destructive path collides with Kakihara, a sadomasochistic yakuza boss with a penchant for pain, it ignites a bloody spiral of chaos, depravity, and unimaginable brutality.