This article explores the history and current laws of sibling marriage in Japan, as well as cultural attitudes towards it, potential social repercussions of marrying a sibling, legal options for those who wish to do so, and what to consider before making such a decision. It is illegal to marry one's sibling in Japan and carries a prison sentence if convicted. Additionally, couples may face significant social stigma from family members and peers alike should they choose to pursue this option. However, there are still ways for couples wishing to get married legally without fear of prosecution provided they meet certain criteria set forth by local authorities.