Halloween costumes are worn on or around halloween which is on October 31. Wearing costumes and masks for Halloween dates back to Celtic traditions. The idea was to copy the evil spirits in a certain way.
Most costumes follow that very same premise by imitating scary or spooky things or people however girls nowadays enjoy dressing up in a more revealing and attracting costumes.
The sexy costume at present day is a combination of a few outfits. Many involve lace or lingerie in which a lot of skin is revealed.
Couples
People in a relationship might where a couples costume in which the girl would wear a sexy costume that accents her dates costume.
Such as: GI Joe and GI Jane Doctor and Nurse Tarzan and Jane Vampire and Helpless Victim Hugh Hefner and Playboy Bunny Cowboy and Cowgirl