Mélusine's Mother casted a spell on her. It was supposed to be only broken as Mélusine was finding a man to marry her without seeking to find out her secret on Sabbat's day. Mélusine Married Raymondin and maked him promise that he would never try to see her on Saturdays. They had ten boys.
One day, Raymondin transgressed the rule by entering is wife's room. He saw her "having a bath in a large marble tub, she had a woman's body to the navel and was combing her hair. From her navel was beginning a snaka tail." Mélusine run away and Raymondin never saw her again in human body.