Ji is synonymous with women, usually related to the place where they were born or lived. For example, Nobuhiko Oda's wife, Keanu, is from Niigata, so she is called Keanu. For example, Toyotomi Hideyoshi's youngest wife Dianji once lived in Dianchuan, so she was called Dianji.
Lang, easy to understand, is an adult man. Lang's name has many reasons, for example, he ranks third, or he may be called. As the main heir of the family (usually the son), there are many fixed titles, usually taro, with many exceptions. For example, the heir of the Houbeitiao family, regardless of ranking, is called Xin Jiulang; In addition, the heirs of the Tokugawa family are all called Takechiyo.
The above titles are applicable to samurai families, except for miscellaneous surnames.