Tweet of the Day: God All Up In My Sex
This trope is brought to you by the letters U-S-T. Something prevents a couple from doing the deed, either something fatal to one of them, both or the world. A great way to keep the lovers apart until the climax of the story…
Wait, did I just…never mind.
However, it can also serve as chastity belt, especially for female characters, emphasizing their purity while the males just boink whomever (or whatever) they please. Sex is good for him but bad for her. It can also be a very lazy way of maintaining the sexual tension between characters if not used properly.
So use with care.