Diegetic music

Diegetic music, also called source music, is music that is part of the fictional world portrayed in a piece of narrative media (such as a film, show, play, or video game) and is thus knowingly performed and/or heard by the characters. This is in contrast to non-diegetic music, which refers to incidental music or a score that is heard by the viewer but not the characters, or in musical theater, when characters are singing in a manner that they would not do in a realistic setting.