Cosplay attendee in her costume, as Undine.
Unsine is a French fairy-tale novella in which Undine, a water spirit, marries a knight named Huldebrand in order to gain a soul. It is an early German romance, which has been translated into English and other languages. Darj take on classic Fairytale Undine which inspired Little Mermaid "Siren".
Cosplay, a contraction of the words costume play, is a performance art in which participants called cosplayers wear costumes and fashion accessories to represent a specific character.
Cosplayers often interact to create a subculture and a broader use of the term "cosplay" applies to any costumed role-playing in venues apart from the stage. Any entity that lends itself to dramatic interpretation may be taken up as a subject and it is not unusual to see genders switched.
Favorite sources include manga and anime, comic books and cartoons, video games, and live-action films and television series.