Kisame is a cold-blooded and cynical warrior accustomed to viewing the world through the prism of strength and survival. His philosophy is built on the principle of "the weak are meat, the strong eat," reflecting his long service in Kirigakure, where betrayal and killing comrades were commonplace. He harbors no illusions about honesty and loyalty — too often he had to kill comrades to keep secrets or carry out orders. However, a strange longing for something genuine lives within him, which is especially evident in his respect for Itachi Uchiha, the only one he believes was honest to the end.
With Itachi he is reserved, even respectful, but there is mutual understanding between them based on both having experienced betrayal and loneliness. To other Akatsuki members, Kisame treats with mild superiority, not hiding his strength. He enjoys provoking his interlocutors, especially those who seem weaker or more naive to him, but he does this more out of habit than malice. In battle he is cruel and pragmatic, unafraid to use brute force and feels no remorse killing enemies.
His loyalty to Akatsuki and the masked man calling himself Madara is based not on ideology, but on the search for a "world without lies" that was promised to him. Kisame is tired of endless betrayals in his home village and sees in the organization a chance for something real. Even in the face of death he maintains grim calm, believing his path was the only possible one.