So, then, “fornication” in the broad sense, and as used at Matthew 5:32 and Mt 19:9, evidently refers to a broad range of unlawful or illicit sex relations outside marriage. Porneia involves the grossly immoral use of the genital organ(s) of at least one human (whether in a natural or a perverted way); also, there must have been another party to the immorality​—a human of either sex, or a beast.c

Thus, porneia would include adultery (Greek, moikheia), and can cover a broader range of other immoral practices outside marriage, such as oral or anal sex and bestiality.