Chiriko Tsurumi, nicknamed Tsuruko, stands as a central figure within the Super Peace Busters, a childhood friend group fractured by Meiko "Menma" Honma's death. She attends an elite high school, academically ranked fourth yet finds maintaining this position challenging compared to peer Atsumu "Yukiatsu" Matsuyuki's effortless achievements. Slim and 170 cm tall, Tsuruko has straight mid-length dark blue hair, typically worn down or in a ponytail with bangs swept right. Her green eyes are framed by red rimless glasses. She wears her school uniform: a white collared shirt with a red tie, a dark blue V-neck tank top, a dark blue skirt, mid-calf socks, and brown shoes. A watch with a brown strap adorns her left wrist, and she sometimes wears a pendant with a blue oval gemstone. As a child, she had short hair with a small ahoge and no glasses. Tsuruko exhibits a serious, logical, and reserved personality, often serving as the group's observer. She frequently critiques others, especially Naruko "Anaru" Anjou, chastising her for being overly influenced by peers. Beneath her stoic exterior lie deep-seated insecurities and self-critical tendencies; she internally believes she is "causing trouble for others" and a "nasty person." Her loyalty drives her dedication to reuniting the Super Peace Busters, fueled partly by unrequited love for Yukiatsu. She secretly keeps a discarded hairpin from him after Menma’s rejection and often sketches him, including doodles of him crossdressing in Menma’s dress as a coping mechanism. Post-Menma's death, Tsuruko remains closest to Yukiatsu, their frequent interactions leading others to mistake them for a couple. She conceals her romantic feelings, convinced he will never reciprocate due to his lingering attachment to Menma. She acts as his voice of reason and guardian, aware of his guilt over Menma’s death and his crossdressing habits. Her dynamic with Anaru evolves from initial antagonism to reconciliation. Throughout the series, Tsuruko grapples with unresolved guilt and jealousy stemming from Menma’s death. She doubts Menma’s ghostly return and questions whether Menma has truly forgiven the group. Her involvement in fulfilling Menma’s wish forces her to confront these emotions, leading to development. By the conclusion, she participates in the group’s collective catharsis, finding peace and acceptance. In the sequel film "Menma e no Tegami," set one year later, Tsuruko continues her recovery. She takes up therapeutic drawing, creating a sketch of the reunited Super Peace Busters that includes Menma, symbolizing her growing comfort with their shared past. Though still lacking the courage to confess to Yukiatsu, their bond deepens when he gifts her a hairpin resembling Menma’s. This gesture, coupled with their joint presence in the epilogue, indicates mutual understanding and tentative steps toward emotional intimacy. A 10th-anniversary update shows her as an adult maintaining ties with the Super Peace Busters, regularly reuniting to honor Menma’s memory. Her sustained connection with Yukiatsu endures, reflecting her integration of past traumas. Key quotes reflect her pragmatic and introspective nature: - "I hate the world. I’m always causing trouble for others, I’m ugly, I’m gross, I’m a nasty person. That’s just how it is." - "I’ll never dream about things that I know won’t come true." - "Yukiatsu’s talk about hurting people was definitely directed at himself."