Lust is disordered desire for or inordinate enjoyment of sexual pleasure. Sexual pleasure is morally disordered when sought for itself, isolated from its procreative and unitive purposes. By masturbation is to be understood the deliberate stimulation of the genital organs in order to derive sexual pleasure. The deliberate use of the sexual faculty, for whatever reason, outside of marriage is essentially contrary to its purpose. To form an equitable judgment about the subjects' moral responsibility and to guide pastoral action, one must take into account the affective immaturity, force of acquired habit, conditions of anxiety, or other psychological or social factors that lessen or even extenuate moral culpability.
Fornication is carnal union between an unmarried man and an unmarried woman.
It is gravely contrary to the dignity of persons and of human sexuality which is naturally ordered to the good of spouses and the generation and education of children. Moreover, it is a grave scandal when there is corruption of the young. Pornography consists in removing real or simulated sexual acts from the intimacy of the partners, in order to display them deliberately to third parties. It offends against chastity because it perverts the conjugal act, the intimate giving of spouses to each other. It immerses all who are involved in the illusion of a fantasy world.