A succubus is a type of demon related to Medieval folklore, particularly in the British Isles. A succubus would assume the form of a woman in order to seduce and have intercourse with unwary men. An incubus is the male equivalent, which would seduce women for the purposes of intercourse. In some folk tales, incubi and succubi are able to change gender in order to prey on either victim. In both cases, it is with evil or malicious intent - such as spreading disease, unwanted pregnancy and feelings of sorrow in the victim. Tales of succubi have been used to teach young adults about the dangers of premarital intercourse although some are cautionary tales about giving one's love too freely.