Meiko Shiraki is a third-year student in attendance at Hachimitsu Academy and the Vice-President of the Underground Student Council, a vigilante school organization. Meiko is put in charge of guard duty during the two months that the boys are incarcerated in the school's Prison Block. Meiko is the subordinate and best friend of Mari Kurihara, the president of the USC. Meiko is a tall and attractive young woman with gray hair that she wears in a bun with bangs swept to the right side while she has neck-length hair strands hanging on either side, brown eyes, and a slender but voluptuous body with massive breasts and wide hips. She is usually seen wearing the school uniform with a miniskirt, oval-shaped glasses, tights, knee-length boots and an open collar, showcasing her enormous cleavage. Meiko brandishes a horse-whip for torture methods on the prisoners. Meiko is a highly confident girl who is commonly seen around campus in a scanty outfit and her reputation for being a sadist and a misandrist is well known, especially to the five boys whom she physically punishes during their detention and Takehito Morokuzu is regularly her victim. Meiko has immense physical strength and is a capable combatant, using her physical abilities to loyally aid her best friend and superior Mari Kurihara. During her spare time, she completes a hundred or more squats and push ups and she is capable of many brutal feats of strength.