Flandre Scarlet (フランドール・スカーレット Furandōru Sukāretto?, alternate spelling Frandre Scarlet, Frandle Scarlet)
Ability: Destruction of any and everything
Residence: Scarlet Devil Mansion
Theme Song: U.N. Owen Was Her?
Title: The Devil's Little Sister
Extra stage boss. Remilia's little sister, sealed away in the basement of the mansion for 495 years because of her destructive power. Despite this, she likes her sister and doesn't usually try to escape. Most vampires hold back somewhat when fighting humans, as they plan to keep them alive and feed from them later, but Flandre was always fed prepared dishes and does not know her food comes from humans. Thus, when fighting them, she does not hesitate and incinerates them without a second thought. In dōjinshi, she is very fond of Marisa and is often portrayed as somewhat crazy for being locked up for so long.
Her theme music, "U.N. Owen Was Her?", is a popular Internet meme and has inspired hundreds of remixes, most notably a video which has Ronald McDonald sing the song using clips from Japanese McDonald's commercials