Victor Hugo writes that she has never told a lie in her life because it is sinful to do so. However, later on in the book, Sister Simplice lies twice to Javert to protect Valjean. The chapter on which Fantine dies is from her point of view, and according to her monologue, Fantine similes as Valjean promises to rescue Cosette
Sister Simplice is described as being "white, with a waxen pallor" and having an age that was impossible to tell. According to Victor Hugo, "she was a person--we dare not say a woman--who was gentle, austere, well-bred, cold, and who had never lied."