Black Peacock was a person with a strong will to survive, always prioritizing his own safety above all else. His fear of death could be gleaned from his mastery of the Invisibility Technique.
He was a core member of the organization, and there was no hierarchy between him and the other core members. Including the elusive leader, they all hold equal rankings. Joining the organization as a core member didn't have many explicit restraints, so Black Peacock had no qualms about surrendering.
Despite no core member of the organization having been captured by other forces since its establishment, he had no intentions of being the first. Needless to say, his life certainly held more value.
Kneeling on the somewhat intact gray floor, Black Peacock held his hands high in a sign of surrender. As he was under no pressure or any scheming whirling in his mind, his gaze was strangely clear and candid. He was clearly expressing to everyone that he wanted to surrender.