Yaoi, also known as Boys' Love, is a Japanese popular term for female-oriented fictional media that focus on homoerotic or homoromantic male sexual relationships, usually created by female authors. As yaoi works depict sexual relationships between males, the genre attracts an androphilic male audience as well; however, manga aimed at a gay male audience (bara) is considered a separate genre. The genre also attracts lesbian, bisexual and questioning female readers, and several prominent yaoi authors are lesbian.

The main characters in yaoi usually conform to the formula of the seme (top, or dominant figure) who pursues the uke (bottom, or passive figure). Material classified as yaoi typically depicts erotic gay relationships between attractive male characters. Although the yaoi genre is also called Boys' Love (commonly abbreviated as BL), the males featured are pubescent or older. Works featuring prepubescent boys are labelled shotacon, and seen as a distinct genre.

Yaoi began in the dōjinshi (fan fiction) markets of Japan in the late 1970s as an outgrowth of shōnen-ai, also known as Juné or tanbi, a sub-genre depicting platonic relationships between pubescent or pre-pubescent boys. Yaoi initially emerged as a sexualized parody of popular shōnen-ai anime and manga stories. Over time, yaoi came to be used as a generic term for female-oriented manga, anime, dating sims, novels and fan fiction works featuring idealized homosexual male relationships. The genre has spread beyond Japan, and both translated and original yaoi works are now available in many countries and languages.