Oshizu Hebimori occupies seat 15 in Class 1-3 at Roubai Girls' Academy. Her defining passion is punk rock music, fueling a strong desire to learn the guitar. Initially, she can't read sheet music and has never properly played the instrument, but she gradually develops her guitar skills over time. She shares a dorm room with Mai Togano. Oshizu communicates in a direct, colloquial manner, which sometimes causes her difficulty understanding more formal speech, like that of her classmate Erika Kizaki.

Serpentine motifs define her character design, reflecting the meaning of her surname ("snake forest"). This theme appears in her accessories, such as a snake-shaped hair clip, and occasionally surfaces in her artistic expressions. Oshizu navigates her school life and interactions with peers, engaging in personal interests like music as part of the ensemble cast.