Lady-in-waiting
A fake title given to someone who shows up at a wedding but has no idea what a wedding is. They just came to eat cake and leave.
My uncle got 'lady-in-waiting' because he showed up in a suit and asked for a drink.
My cousin’s best friend got the title because she brought a cake and left before the speeches.
My grandma got it because she showed up in pajamas and ate all the cookies.