A doushinijija, often referred to as "double in double out," is a term used in the context of Japanese culture, particularly related to the practice of "doushinijija" or "doujinshi." It typically involves the creation and distribution of self-published works, such as manga or novels, by amateur artists and writers. These works often explore original stories or reinterpret existing characters and narratives from popular media, fostering a vibrant subculture of creativity and fan engagement.