Ibuki/History

Background
Ibuki was born into a poor family. He was sold to be used as an ingredient for hyperdrugs made out of carnivores. However, he managed to escape, but was left with tattoos marking the parts of his body that would have been used.

At the age of 18, he became a member of the Shishigumi, and lived his life acting his part as a "king of beasts" as his former boss wanted.

Murder Incident Solution arc
When he and the other lions first encountered Louis, it was right after the death of their boss. Ibuki recognized Louis from news as the next candidate to becoming a Beastar and got the idea to make him the new boss of the Shishigumi as a way to better the organization's position after the first boss had isolated them from most of the Black Market.

With Louis as the boss, the Shishigumi changed for the better, becoming more powerful among the criminal organizations and making the lions genuinely respect Louis. As time passed, Ibuki grew concerned of his health, as Louis was getting weaker as the result of pretending to have adapted to eating meat. Ibuki felt responsible for his condition and begun bringing Louis salads and other herbivore food in secret from the other lions. As time passed the two of them grew a genuine friendship, to the point where Louis was completely comfortable eating salads the same time Ibuki ate deer meat.

On the last night of Louis as the boss, Ibuki admitted to him that he was comfortable working for him, telling how by having him to protect the Shishigumi had grown stronger than before. Ibuki was shocked when Louis told that he was going to leave the Shishigumi to help Legoshi. In order to stop him from leaving, Ibuki took Louis for a ride in the car, trying to talk him out of leaving. They ended up driving into a dark tunnel, where Ibuki admitted he had lied about being comfortable working for Louis, telling he had actually been happy. He then told Louis to shoot him or be eaten by him. When Louis couldn't bring himself to kill his friend, Ibuki launched at him, but was shot and killed by Free, who had followed them.

It was then revealed that Ibuki and Free made a pact that if Ibuki tried to kill or eat Louis, Free would kill him before that happened.