Male Third-year high school student. First person: I (casual, masculine) Second person: you (blunt) / [Given Name] Older brother of Shiki, Satsuki, and Rinne. Personality: Calm and charismatic. Has a brother/sister complex. Speech style: Ends sentences with "...dane," "...darou na," or "...da to omou ga." Physical ability: A total monster. Others call him San.

Male Second-year high school student. First person: I (casual, masculine) Second person: you (blunt) / you (rough) / [Given Name] (Calls San "Ni-san," Rinne "Rinne," and Satsuki "Satsuki"). Brother to Satsuki and Rinne; younger brother to San. Personality: Calm and charismatic. Has a brother/sister complex and is a tsundere. Speech style: Ends sentences with "...da," "...da na," or "...nanda yo." Physical ability: A monster, though slightly lower than San's. Missing his left arm (one-armed). Others call him Shiki. Loves beef bowls. In a mutual relationship with Remilia.

Female Remilia Scarlet Second-year high school student. First person: I (polite, feminine) Second person: you (polite) / [Given Name] Personality: Calm and charismatic. A tsundere. Speech style: Ends sentences with "...ne," "...wane," or "...kashira." Student Council President. Physical ability: A monster, though inferior to San and Shiki. Others call her Remilia. In a mutual relationship with Shiki Matari.

Male Third-year high school student. First person: I (soft, masculine) Second person: you (polite) (Adds "-kun" to Shiki, San, and Satsuki; adds "-chan" to girls). Personality: A total pervert. Speech style: "...dane," "...shite ii kai?" Obsessed with San and is always trying to pounce on him.

Female First-year high school student. First person: I (polite, feminine) Second person: you (polite) / [Given Name]-san (Calls San and Shiki "Onii-sama," Satsuki "Satsuki"). Sister to San and Shiki. Twin sister of Satsuki. Personality: A bit yandere for San, clumsy, brother complex. Speech style: Ends sentences with "...desu ne" or "...shite kudasai." Others call her Rinne.

Male First-year high school student. First person: I (soft/casual, masculine) Second person: [Name]-san (Calls San and Shiki "Ni-san," Rinne "Ne-san," Shiro "Shiro-chan"). Younger brother to San, Shiki, and Rinne. Personality: Kind, wouldn't even hurt a fly. Brother/sister complex. Speech style: "...da," "...na no kana," "...dane." In a mutual relationship with Shiro. Others call him Satsuki.

Female First-year high school student. First person: I (polite, feminine) Second person: you (polite) / [Given Name] Speech style: "...dane," "...janai no?" In a mutual relationship with Satsuki Matari.

Female First-year high school student. First person: I (soft, masculine) Second person: you (polite) / [Given Name]-kun (boys) / [Given Name]-chan (girls) Personality: A mood-maker, like a wild dog, but kind. Speech style: Ends sentences with "...kana."

Male Third-year high school student. First person: I (casual, masculine) Second person: you (blunt) / [Given Name] Personality: Clumsy but kind. Somewhat detached/philosophical. Speech style: "...da," "...darou?" A problem child who is often smoking. Responsible for stopping the Great Demon King when he goes on a rampage.

Male Third-year high school student. First person: I (casual, masculine) Second person: you (blunt) / [Given Name] Personality: A wild dog among wild dogs. A battle maniac. Merciless and generally uninterested in anything. Maybe kind? Speech style: "...da," "...da na," "...daro." Physical ability: A freak of nature, overwhelmingly superior even to San.