If you read the story that accompanies these photo captions on Yahoo! Style (but really, why would you?) you’d learn that there was only one groom at this wedding. So, it looks like the writer had no idea where to put the apostrophe to show a possessive. It ain’t here:
and it ain’t here:
At least she was consistent, which is more than I can say when in comes to spelling the groom’s party attire — somehow it’s both bow ties and bowties.