I don't really find ANY holidays to be sexy, except Valentine's Day. Even Halloween, I have to say, "If it's separated from the holiday for kids." But I've enjoyed some sexy costumes with my partners! Of course, Halloween is just the best holiday in all existence.
It kind of creeps me out when people wear sexy "Mrs. Claus" costumes and so on. XD But that's just because Santa Claus scares me a little.