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"Intentionally views." The deliberate, purposeful, voluntary viewing of material depicting a child under 18 years of age engaging in a prohibited sexual act or in the simulation of such act. The term shall not include the accidental or inadvertent viewing of such material.
"Prohibited sexual act." Sexual intercourse as defined in(relating to definitions), masturbation, sadism, masochism, bestiality, fellatio, cunnilingus, lewd exhibition of the genitals or nudity if such nudity is depicted for the purpose of sexual stimulation or gratification of any person who might view such depiction.
18 Pa.C.S. § 6312