Hook is Beige "white" Labrador Retriever mix with dark brown patches and stitched scars on the left side of the nose and left cheek. He has pale reddish-orange eyes. He wears a black collar.
Hook is a quite calm, humble and polite dog. He was mocked by the neighbor dog, Golvy, but didn't get too angry by it, since he is a former wild dog and understands things much better than his neighbor. Hook is seen to be helpful and gave food and information to Weed and Lenny. However, he mentioned he does this due to his hatred towards Blue, Ned and Bell. As a pup, he was manipulated by Blue and his minions to be loyal and steal for them. He was extremely bitter towards them after they killed his brother but he developed fear towards them as a pup and was unable to face them due to this. Eventually, he gathered his courage thanks to GB and Weed. He also leaves his life as a pet, as he never liked it. He is very thankful for Weed and promises to come to help him if he needs him. Hook is quite brave and not afraid to stand for what is right. Still, he admits he was a bit afraid when John was killed.
Hook was abandoned as a puppy and, together with his brother Kuro, he joined the three rogue dogs named Blue, Ned, and Bell for protection. One day, Hook’s older brother questioned Blue about stealing and got killed for doing so. Hook ran away and became a pet in the town nearby. When Hook met Weed, he felt courage run through his veins. He decided to take part in the battle with the three rogue dogs to avenge his brother's death. He gathered other town dogs and launched on an attack. His mission succeeded when Blue ran out in front of a truck and got run over. Afterward, Hook returned to his owner but decided to follow Hōgen’s minions out of curiosity when they come to town to round up dogs. Hook hoped to be of use and gathered important information for Weed. Here he met Sasuke, whom he found out was also on Weed’s side. Hook was a witness to the murder of the German Shepherd, John, and decided to join Weed’s group to defeat the tyrant Hōgen. Unlike the anime, he follows Weed's group together with Reika (who had been freed by Hiro, John, Lefty, Rossy, and Tommy) and Sasuke throughout the manga on their journey.
Formerly a pet, and a slave to Blue before that, he escaped and helped save Mercedes from Blue. He was working for Weed independently. One day, a month after the Monster's death, he was seen by Nero and was beaten by his dogs.They kept beating him until Gin, John, and Akame came and saved him. At first, he mistook him for Weed, but realized that it was the father of Weed. He was the one that told Gin about Weed, and helped Gin in secret during his imprisonment by Hōgen. He brought Reika to the hideout below Gajō after he witnessed John's death.
Hook and other Ou armys have caught in the volcanic eruption. He and Ou dogs are in a shed in the mountains, saved by Kurohabaki Jinemon. They stay there until rescued by Daisuke and Hidetoshi. Hook follows the group back into the mountains to find Weed. They participate in the final battle Kurohabaki Masamune against the packs.
Hook is among the dogs during their era of peace when Monsoon attacked and badly injured most of them, killing a few in the process. Hook fights the bears but is badly wounded and placed in a makeshift prison with the surviving dogs. After spending a few days in the prison, he notices Mole, the son of Oliver, digging through the floor to reach them. Hook is supported by Mole as he takes him to a patch of forest where the rescued dogs are recovering from their wounds. Many days later, Hook and the rest of the dogs are rescued by Mole and his group. Barely able to walk due to injuries and being cramped in the prison for so long. Shortly after, Hook and other Ou soldiers are resting in the grass during a storm. Then, Hook and the others see Monsoon coming along with Kagetora he is the next one to stand up and willing to sacrifice himself for his comrades. After Kage's attack against Monsoon he sees the bear fleeing for his life. He discovers from Akame that Monsoon ran away because of the arrival of humans. Shortly after he and the others heard a helicopter from up above, upon seeing it Hook wishes for the humans to give Orion and the others support. After the rest of Monsoon's Kin is dead, Hook and the others hears their comrades howling for victory and decides to join in too. Next, Hook is seen sleeping in the grass unaware how much time has passed and he goes to see if everyone is alright to which they are. Then, he is alerted by Kurotora that someone is coming thinking it was Monsoon and Akakama stands up to defend them. It turns out it was Orion and Tesshin who tells them that they found Monsoon again but he got away. Once Akakama hears that he points out that they scared him leaving Mel shocked that the dog was afraid. He hears Orion says he'll never forgive Monsoon for what he did and won't let him get away. Hook and the others see hunters searching for any remaining bears as well as take their fallen comrades away for burial and Kurotora tells them not to be afraid and that these humans are they can trust. The Kai Ken tells them not to bite the humans especially Akakama he warns him that if makes enemies they can't work together. Then, he is treated by Daisuke for his injures along with the others Hidetoshi couldn't take in. With his wounds healed, he and the other injured dogs regroup and are joined by Gin, who left Daisuke's care to check on them. Feeling defeated over their losses, the army spend their days and nights cuddled together for comfort before Andy, Yamabiko, Bon and Orion leave to find Sirius. When morning comes Hook hears Kyoshiro chew Orion out for sending his friends away and then watches the fight by Orion and Kyoshiro even though the kishu lost. He saw Orion crying in tears saying that he stayed behind for the sake of everyone because the Ohu Army needs a true leader. After Orion's returning visit from Akame and the others, he hearsthat everyone is doing well. Hook goes with everyone to search for the lost sickle but after days of searching it's nowhere to be found. With Kyoshiro thinking that Orion isn't leader material anymore they all choose Cross to be the new boss with Kuro agreeing and when Orion returns. He hears Orion say that he is going to learn some new secret ninja techniques he picked up from Akame. Believing in the young pup he follows the others to watch Orion. Seeing Orion's skills, Hook and the others want to try it too, but when they try to take a swing, they don't manage to do the same as Orion. He hears from Orion what he learned in a day took Akame two years to learn. As the training continues, he becomes impressed with Orion's progressed and gets encouraged to keep training. Then, he hears that Rigel and Rocket have returned, but with them are a bear cub. Everyone charges at it, after Kyoshirou attacks it. When he attacks the bear cub, he becomes surprised that Rigel flipped Kyoshirou over with ease. After Rigel explains everything, they all become surprised that Sirius wants them to raise Chibi until he becomes an adult. Hook watches Rigel and Rocket convince Orion not to kill Chibi. Then, he hears Kurotora batter Orion for his attitude. When he hears that Orion is trying to protect everyone in Ohu Kuro says that he doesn't need protecting from him. He also sees Orion pointing his bamboo stick at the kai ken convincing the pup to attack him but is stopped by Jerome and watches in horror as Orion almost attacks the shepard. He watches Kyoshiro give Orion a beat crying in tears and Mel restrains him but soon the tears turn into laughter as everyone runs back up the hill.
- in GDWO Hook is only seen in the first chapter
- Some fans think Hook is a mix between a Labrador and a Dalmatian, but nothing is confirmed.