Vai. Mu. Kothainayaki Ammal

Vaithamanithi Mudumbai Kothainayaki Ammal (1 December 1901 – 20 February 1960), familiarly known as Vai Mu Ko, was an Indian writer, novelist, and journalist who was the first woman to occupy the editorial board of a Tamil magazine. She wrote 115 books and published a monthly Tamil magazine, Jaganmohini.

Kothainayaki was the first female writer in Tamil to write a detective novel. She was interested in a variety of topics and excelled in fields like public speaking, social service, music composition, and fiction writing. Kothainayaki was also a feminist and a freedom fighter. She was hailed as the "Queen of Fictions" by contemporary authors. However, Kothainayaki was not well recognized in books about the history of Tamil literature.