Daenerys may have been Drogo's Moon of My Life, but my girlfriend She-Ra: Princess of Power is my entire solar system. So I think I might get her one of these interchangeable planet bracelets for her birthday this year. They come with 10 magnetic centers, one for all 8 planets of our solar system, plus the moon and sun. Swap them out according to your mood or do what She-Ra does and match them to the color of your eyes, purse, or yoga pants that day. Maker Jerseymaids says the planets' magnetic pull is very strong (another reason I want to buy one?) so they won't fall out of their setting when in place. Planets not in use during wear can be attached to the fridge.
Another reason the interchangeable planets bracelet makes the perfect gift for my girlfriend is that it looks nice and expensive in its antique bronze or silver tone band, but doesn't actually cost very much at all. For an extra $2 you can even buy Pluto back from planetary banishment and have him included in the set.