A person under eighteen years of age shall not perform in or be a subject of sexually explicit visual material. As used in this section, “sexually explicit visual material” means a picture, photograph, drawing, sculpture, motion picture film or similar visual representation which is obscene for children, as defined in § 18.2-374.1, and which depicts nudity, sexual excitement, sexual conduct, sexual intercourse or sadomasochistic abuse, as defined in § 18.2-390, or a book, magazine or pamphlet which contains such a visual representation. An undeveloped photograph or similar visual material may be sexually explicit material notwithstanding that processing or other action is necessary to make its sexually explicit content apparent. A person who employs, permits or suffers a person to be employed or work in violation of this section is guilty of a Class 6 felony.