Catechism of the Catholic Church §2355 — excerpt
Prostitution does injury to the dignity of the person who engages in it, reducing the person to an instrument of sexual pleasure. 139 Prostitution is a social scourge.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.