Criminalizes INCEST and prescribes stiffer penalties for violation thereof. Defines "incest" as an act committed by any person who marries or purports to marry, or cohabits, or engages in sexual intercourse or acts of lasciviousness with anoather person whom he/she knows to be his/her ancestor or descendant by blood or adoption, regardless of degree, or his/her stepchild, while the marriage creating relationship subsists, or his/her brother or sister, whether of the full or half-blood, or his/her collateral blood relatives, whether of the full or half-blood, up to the fourth civil degree. Defines further "acts of lasciviousness" for the purpose of this Act.