Last name 忍者 (Ninja 
, 忍者 
, Ниндзя 
) , worldwide, is quite a rare cognomen. The cognomen 忍者 is characteristic of Trinidad and Tobago, where it is quite a rare surname, Serbia, and Nepal, where it is a rare surname. Not in comparison with a country's population, this name is the most popular in Indonesia, Nepal, and Kenya. Likewise, 忍者 is the forename as well as the last name.