Natsuo Kirino is a Japanese author renowned for her dark, suspenseful fiction that often examines the lives of women under social and psychological strain. Born Mariko Hashioka in 1951 in Kanazawa, she worked in various fields, including advertising, before turning to writing. Her experiences in everyday workplaces helped shape the realism and intensity of her stories.

She gained international acclaim with her novel Out (1997), which won the Naoki Prize and was later translated into multiple languages. Known for exploring themes like alienation, identity, and societal pressure, Kirino has become a leading voice in contemporary Japanese crime fiction, with works such as Grotesque and Real World further cementing her reputation.