"The Lamentations of a Mermaid" (Ningyo no nageki) is a literary bar ("Bundan" bar) in Tokyo. You can meet writers, novelists, editors and other people from the literary circle in the bar.
The name of the bar is taken from the novel by Junichiro Tanizaki. The bar is owned by Ms. Saiko Matsumoto.
Literary bars such as The Lamentations of a Mermaid are Japanese institutions. There are many legends involving famous writers in the literary bars. Literary bars are also practical in that you can have a chance meeting with people who share the same interest, namely writing and editing. Sometimes, projects for a book is struck up in the bar.
The Lamentations of a Mermaid is located near the University of Tokyo. I know the area very well from my student days. There are many second hand bookshops, where they sometimes sell the original hand-written manuscripts of famous writers.
The sign ("The lamentations of a mermaid" written in Japanese) at the door of my favorite literary bar.