10. Fairy Floss
Also known as cotton candy, of course! Buy some at the store for about $1 and add it to your pink shirt (and your hair, if you dare; you ould alwas stick it on a headband) for a quick, easy costume.
9. General Fairy
Add some glitter for a quick fairy costume; if you have a wig and wings, even better. You can also make a simple wand, or use your kid's Harry Potter replica.
8. Pink Elephant
Remember that trippy dream Dumbo had when he got drunk? (I'm pretty sure that's what happened; it's been a while.) Make a long trunk out of a pink sweatshirt sleeve, ears out of the front and back of the shirt, and a tail from the remaining sleeve. Put on another pink shirt and you're done!
Pink is one of those peace and love colors, right? Add a pair of jeans and a headband and you're done--or take it further with some jewelry, sunglasses, and a protest sign.
Nobody really knows what Cupid might really look like, so just use your imagination and have fun with this. Maybe you could add a bunch of hearts to the shirt, or have them dangle from it with fishing line. Along the same line, you could also be his mother Venus/Aphrodite.
5. Nymhadora Tonks
Write "Weird Sisters" on the shirt and muss up your hair any way you like. You could even dye it any color, though fans know her favorite shade is pink.
You could be a romantic gift for someone in your pink shirt and cardboard heart cutouts, sure--or you could go grisly and be "My Bloodly Valentine" by adding a bunch of fake blood and either homemade Valentine cards or storebought ones from last year.
3. Love Train
Draw a big heart on your shirt and have several friends do the same and connect to randomly sing the song in a Halloween flash mob.
Drawa martini glass on your shirt and voila, you'e a Cosmopolitan.
Whether you're Piglet from Winnie the Pooh or just an average pig, you can draw or get a cheap pig snout and ears and you're good to go. For creepier pig (a la Hannibal), add some fake blood.