The story ends during a wedding. The story must have a werewolf in it. During the story, a character eats something that disagrees with them.
When they got engaged, Gary told Jill that she could plan the whole event. "Just tell me when to be where!", he had said. When he got bitten, he gave her a list of dates and said "Uh, I gotta be in a cage these nights - full moon. Otherwise, I'll eat people. And man, you do *not* wanna have to deal with the gas that gives me."
He sort of lost track of when the wedding was, but he showed up where and when he was supposed to. He realised somethign was wrong about 30 seconds past the "if anyone knows a reason why these two should not be wed" part.
Gary could have sworn the priest said "You may now eat the bride".