"Gender bender" tends to be used as a catch-all term for transgender (and sometimes intersex) people, but for the purpses of this wiki, it will mean this: individuals whose sex has been changed through technological or magical means to be wholly the other sex (including reproductive organs and other such things modern science just cannot do). The nature of this situation in the media is that it is usually done to an unwilling participant. However, those who are willing may choose to have it happen as well.
This is also a (more or less) permanent change. For characters who change sex only in order to fight crime, there is a category for that (Super gender bender).
Sometimes this category will be called TG, but such is a misleading title, due to this also simply being the abbreviation for "transgender".