Introduction Penal law of a State, depending upon her criminal policy and prevalent sexual mores, forbids a set of consensual as well as non-consensual sexual acts. Such a prohibition, generally, is premised primarily either on the absence of consent, real or presumed, of victim of sexual assault (e.g. rape and unnatural offences) or moral sentiments of the society associated therewith (e.g. adultery and incest). The Indian Penal Code, 1860 (hereinafter IPC), which was shaped between 1834 and 1860 and influenced, to a great extent, by the then common law criminal and penal policies and sexual mores, criminalises rape, buggery with animals, and consensual as well as non-consensual unnatural sexual gratification.1 It does not, plausibly owing to its unfamiliarity with the then prevailing English criminal law system,2 include incest — a consensual heterosexual intercourse between ....