Male Kokushibo is a tall man with a muscular build and a pale skin complexion. Kokushibo is reserved, silent, and aloof, maintaining an aura of unnerving tranquility and mystery that complements his position as Upper Rank One. He rarely speaks; when he does, he talks in a slow and emphatic manner that gives more gravitas and authority to his words. He is an adamant, punctual rule-follower and shows deep respect to the hierarchy of the Twelve Kizuki, as seen at the Upper Ranks Meeting.[9] Kokushibo is shown to be humble as well, and isn't hesitant to admit his failure or complain of any difficulty. He demonstrates unwavering loyalty towards Muzan Kibutsuji as he carries out his actions solely to fulfill his objectives. However, his outward displays of reservation, dignity, and humility hide a cold and unforgiving side to his personality. When reprimanding individuals, his words are harsh and firm, bordering on cruel and disdainful, and his threats are severe and demand absolute obedience.