That would be really sweet for anyone other than me. However, Moon and I first kissed in my dad's kitchen, and the old man and I don't get along.
At a break in the conversation, your SO asks, "Wanna see a magic trick?"
You reply, "Okay, seriously, you need
to stop watching The Dark Knight
every week. I know working in tech support isn't terribly stimulating, but cinema has been around for a hundred and twenty years - there are other movies to see."
"I will ignore that blasphemous statement because I love you. But I was actually referring to a different magic trick."
(S)He holds up a deck of cards and asks you to pick a card, any card. The one you end up with is the Ace of Diamonds. Taking it back, (s)he looks at it and compliments you on a nice choice, before kissing it and asking you to do the same. "The kisses are a necessary magical ingredient in order to activate the transformation spell."
Then (s)he tears the card up, puts the pieces in your front pocket and says, "I'm gonna count to three, and when I do the Ace of Diamonds will be reborn. Ready? One... two... three! Now, look in your pocket."
The pieces are gone, and in their place is a solitaire engagement ring.