Peach Maki is a demon residing in the Japanese underworld, working as a popular idol. Her full name is written as ピーチ・マキ in Japanese. She possesses black hair, brown eyes, and consistently adorns herself with peach-themed accessories. Before her idol career, she worked as a store clerk in the mortal world, developing a profound dislike for shoplifters, whom she labels "shoplifting ghouls" or "that damned old shoplifting ghoul." She also expresses intense aversion to tests and numerical tasks, stating that even contemplating numbers makes her feel physically ill.

As an idol, she performs in the duo "Maki Miki" alongside Miki. Peach Maki occasionally questions the nature of being an idol and finds assigned tasks bizarre, pondering what it truly means to hold this role. Despite these uncertainties, she maintains a cheerful public persona, citing her "unique mind" or perceived clumsiness as distinguishing traits. Her professional activities include stage performances, such as portraying Angel Uguisu in adaptations of the children's anime "Chinese Angels."

She interacts with various inhabitants of Hell. She is acquainted with Hoozuki, the chief deputy of King Enma, assisting him with events like the Goldfish Plant Festival, though she finds goldfish plants unsettling. She also encounters Karashi, a rabbit jailer from the folktale "Kachi-kachi Yama" working in Animal Torture Hell. Karashi admires Miki and requests an autograph from Maki, prompting an unusual incident where Maki signs a deceased person's scalp at Karashi's suggestion.

Her daily life involves navigating challenges like Goban, a feline journalist attempting to fabricate compromising stories about her. She maintains a professional approach to her work, acknowledging that "work's work" despite its inherent oddities.