Definitions by ChocoMonster
Twincest
Incest between twins, also known as "twincest", is a subclass of sibling incest and includes both heterosexual and homosexual relationships. While in modern Western European culture, such behaviour is considered taboo and is quite rare, incest between twins is a common feature in Indo-European, Indonesian and Oceanian mythology, and there are a few societies in which the prohibition on it is limited or it is partially accepted.
Twincest by ChocoMonster August 26, 2012