Adjective Positive incestual Comparative more incestual Superlative most incestual Incestual is the quality of being romantically or sexually attracted to one's relative. Her relationship with her siblings seems kind of incestual. Noun Singular incestual Plural incestuals (countable) A incestual is someone who is romantically or sexually attracted to their family members. She was accused of being an incestual. Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads