This article explores the laws, regulations and cultural norms around marrying relatives in Japan. It explains that marriage has been a part of Japanese culture since ancient times, and is regulated by both civil law and traditional customs. Civil law states that marriage must be between two consenting adults who are not related by blood or adoption up to three generations back. However, there are certain exceptions for close relatives if they meet certain requirements such as obtaining parental permission or court approval. The legal consequences of marrying a relative in Japan are also discussed, as well as how couples can obtain an exception to the law if necessary.