ONA
Description
The character known as the Death Metal Voice is the hidden alter ego of Retsuko, the protagonist of the series. By day, Retsuko is a 25-year-old red panda working as a mild-mannered and unassuming accountant at a Japanese trading firm. She is polite, shy, and often struggles to express her true feelings, which makes her a target for demanding superiors and frustrating coworkers. To cope with the immense pressure and pent-up rage from her daily work life, she secretly transforms into her Death Metal Voice persona, typically at a local karaoke box or, in emergencies, a bathroom stall.

This transformation is both psychological and visual. When she begins to sing, her usually gentle demeanor is replaced by a fierce, intense expression, often depicted with glowing eyes, an exaggeratedly long tongue, and a fierce visage that resembles black metal corpse paint. The Japanese kanji for "retsu," meaning rage or fierce, appears on her forehead. This persona serves as her primary mechanism for emotional release. Through guttural, unintelligible screaming and powerfully distorted vocals, she belts out lyrics that directly address the source of her frustration, whether it be a sexist boss, a thoughtless colleague, or a personal disappointment.

The Death Metal Voice is not a separate character but the unfiltered, cathartic expression of Retsuko's inner self. Her core motivation is survival and emotional regulation; she uses this extreme outlet to purge the anger she cannot safely display in the office, allowing her to return to her professional life as a model employee. Over the course of the story, this secret ability evolves from a private coping mechanism into a powerful tool for personal growth. While initially a secret she hides from everyone, she eventually uses it to confront her bullying boss, Director Ton, leading to a new level of mutual understanding and respect. She also uses her Death Metal voice to end a relationship that wasn't right for her, singing her true feelings to an incompatible boyfriend named Resasuke to achieve closure.

This persona becomes central to her relationships, serving as a litmus test for genuine connection. Her friends, the secretary Washimi and the marketing director Gori, become her biggest supporters after she reveals her secret to them, encouraging her to use her voice. Her eventual partner, Haida, is also fully accepting of this part of her. In a notable display of power, the Death Metal Voice is shown to have a tangible, almost comical force, capable of blasting a person through a window, demonstrating that her inner rage is a real and potent energy. As Retsuko matures and learns to assert herself in her daily life, she relies less on the Death Metal Voice as her only outlet. However, it remains an integral part of who she is, a testament to her resilience and a powerful symbol of finding strength in vulnerability.