Between the hours of 9am and 7pm Isabel Losada will stay put in the window display of WHSmith on Paris' iconic Rue de Rivioli and will even eat her meals in the space, the publisher told AFP.
The author of "The Battersea Park Road to Enlightenment" is promoting the French release of the book in a stunt reminiscent of a 2010 performance art piece at New York's Museum of Modern Art (MOMA).
Between March and May, artist Marina Abramovic stayed immobile and silent for seven hours straight, six days a week, while museum-goers took turns sitting opposite her and holding her gaze.
Some MOMA visitors sat for hours on end, several cried and celebrities such as singers Bjork and Lou Reed sat in for a shift.
In 1995, Oscar-winning British actress Tilda Swinton lay in a glass box in London's Serpentine Gallery for a week as an art installation.
The publicity stunt by Losada, whose books have sold more than 200,000 copies in 16 countries, also echoes a 2011 Christmas event at Paris department store Galeries Lafayette in which singers performed in the window display.
Losada is promoting the French release of a book in which she chronicles her pursuit of well-being and enlightenment by passing from seminar to convent to tantric sex to a "rebirth".