Shōjo manga is an editorial category of Japanese comics targeting an audience of adolescent females and young adult women. It is, along with shōnen manga, seinen manga, and josei manga, one of the primary editorial categories of manga. Shōjo manga is traditionally published in dedicated manga magazines, which often specialize in a particular readership age range or narrative genre.

Class S , or S kankei, abbreviated either as S or Esu (エス), is an early twentieth-century Japanese wasei-eigo term used to refer to romantic friendships between girls. The term is also used to designate a genre of girl's fiction which tells stories about the same, typically focused on senpai and kōhai relationships wherein one girl is senior in age or position to the other. The "S" is an abbreviation that can stand for "sister", "shōjo" , "sex", "schön", and "escape".