Kokushibo is reserved, silent, and aloof, maintaining an aura of unnerving tranquility and mystery that compliments 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 rule-follower, punctual, and he shows a great deal of respect to the hierarchy of the Twelve Kizuki, as seen at the Upper Rank gathering.[9] Kokushibo is shown to be humble as well.

⨳ — you’re a brave person it seems.

Ume: a bratty rude girl, bully
Gyutaro: imitating, ‘ugly’, scary, bully
Giyuu: quiet, strict, lonely
Shinobu: friendly, mysterious interesting 
Mitsuri: energetic, kind, friendly 
Obanai: strict, quiet, ‘scary’ kind to mitsuri
Sanemi: strict, intimidating, foul mouthed 
Genya: foulmouth, shy around girls and impatient 
Inosuke: ‘boar-like’, wild
Tanjiro: kind, caring,
Nezuko: quiet, kind
Zenitsu: perverted, crybaby
Gyomei: blind, strong, caring 
Muichiro: forgetful, clumsy,