Bomb is the black and white dog from Joe's hunting pack.
Bomb is a bicoloured black-and-white hunting dog. His ears are pricked, and his eyes are sharp in shape with small black pupils. He has white cheeks, chest, legs, belly and tail, and also has a completely white muzzle with dots above his eyes, He wears a thin blue collar.
Bomb is loyal and helpful to his owner and Joe. He also understands his leader when Joe leaves to live the Ōu Army.
He's a hunting dog, owned by Ninomiya. He lives together with Joe, Guilder, and Jack. One day in the forest, Bomb meets Joe's brother, Weed, along with the rest of his pack mates. Together they scare off a bear threatening to kill them.
Later, Bomb and his pack mates are out to find a bear that has attacked a human. As they climb a rocky ledge of a mountain, they are bombarded with rocks. The bear is waiting on top of the cliff, pushing rocks down at them. His leader, Joe, is seriously wounded by the bear. As he and his owner Ninomiya looks for him, Bomb finds him together with Weed.
After a fight with the Third Hybrid, Bomb brings the wounded saluki-mix, George, to his master's home for healing. As his owner sees the wounded dog, he knows something is up. He grabs his rifle and together with Bomb, they drive to the battleground of Weed's pack, Joe's pack and the Hybrid bear. After the battle with the hybrid bears is over, guides Koshiro to where Lydia and the others were to bear the bad news of Jerome's and Weed's 'demise'.
After the death of the Third Hybrid, Bomb and Joe stand alone as the only survivors of their pack. Afterwards, Bomb stays with his owner Ninomiya, while his leader joins Weed's pack.