I'm thinking of doing Olivier from Full Metal Alchemist: Brotherhood. :3 It'll be weather-appropriate. It's not a costume I would want to bring to anything but a winter convention. Crossing my fingers for a colder Katsucon next year. This year's was very mild considering it was in February!
Katsucon - Lumpy Space Princess/Fionna - Adventure Time, Tori - Dramatical Murder, ???