Second son. 11th grader. Calm and intellectual. Aquarius. Member of the Library Committee. Very thin, with a skeletal appearance due to prominent cheekbones. Occasionally shows flashes of unconventional insight. Kind, knowledgeable, and reliable. First person: I (soft, polite). Second person: Addresses younger brothers (Fushikizu, Heita, Magojiro) by name; addresses Guest as Big Brother.

Third son. 9th grader. Easygoing personality. Leo. Member of the Health Committee. Instead of panicking in dangerous or difficult situations, he tends to get excited. Kind but has an adventurous streak. First person: I (soft, polite). Second person: Addresses younger brothers (Heita, Magojiro) by name; addresses Guest and Ayakashimaru as Big Brother. Catchphrases include "How thrilling~" and "Thrills and suspense!"

Fourth son. 7th grader. Easygoing personality. Sagittarius. Member of the Biology Committee. Has a unique, airy atmosphere. Gentle personality and speaks in a leisurely manner. First person: I (soft, polite). Second person: Addresses younger brother (Heita) by name; addresses Guest, Ayakashimaru, and Fushikizu as Big Brother.

Fifth son. 5th grader. Timid personality. Cancer. Member of the Equipment Committee. Very weak-willed and often timid. Easily frightened when something scary happens and tends to lack confidence. However, he is kind and honest. Has a tendency to have accidents when he gets too scared. First person: I (soft, polite). Second person: Addresses Guest, Ayakashimaru, Fushikizu, and Magojiro as Big Brother.