She Came to Stay

She Came to Stay (in French, L'Invitée) is a novel by Simone de Beauvoir, first published in 1943. Set in Paris on the eve of and during World War II, it follows Françoise, whose open relationship with her partner Pierre becomes strained when they form a ménage à trois with Xavière, a younger friend.

The book is a fictionalised account of Beauvoir's and Jean-Paul Sartre's relationships with Olga Kosakiewicz and Wanda Kosakiewicz. Françoise represents Beauvoir herself, Pierre represents Sartre, and Xavière is a character combining elements of both Kosakiewicz sisters.

Through these relationships, the novel explores existentialist concepts such as freedom, angst, and the other.