Retsuko is a timid, hardworking red panda who often finds herself buried in office tasks, taking on more than her fair share. Polite and soft-spoken, she hides a fiery temper fueled by frustration. To cope, she secretly rents a karaoke room and unleashes her emotions through intense death metal singing. Though she's kind and diligent, Retsuko struggles to balance her reserved nature with the fierce side she keeps hidden, fearing others might judge her if they knew the real her.