Natsuo Kirino (born in Kanazawa, Ishikawa Prefecture) is the pen name of Mariko Hashioka, a Japanese novelist and a leading figure in the recent boom of female writers of Japanese detective fiction. Kirino is the middle child of three. She has two brothers, one who is six years older and one who is five years younger. Her father was an architect. Kirino has lived in many different cities, including her current residence, Tokyo. Kirino married in 1975 and had a daughter in 1981. She earned a law degree in 1974 from Seikei University, and she dabbled in many fields of work before settling on being a writer. For example, not knowing what she wanted to do in life, Kirino began working at the Iwanami Hall movie theater in her early twenties. She soon discovered it wasn't right for her and just before her thirtieth birthday she started taking scriptwriting classes. It wasn't until she was in her thirties that she began to seriously think about becoming a writer, and it wasn't until her forties that she became popular as a writer. - Wikipedia