you're a doll 

something you say to someone when they've done something nice, and you feel obligated to acknowledge the gesture even though you don't like them at all.

annoying girl: hey, because you are my friend, I bought you this "best friends" necklace!!!
"friend": Awwww! (exaggerated) You're a doll!

you're a doll by Amy March 16, 2004

you're a doll 

Where I come from you say this in a sense like it's a sarcastic gratitude; like, thanks for putting my books away, you're a doll. Can also be used in a sexual connotation, like, you're a doll, babe.

you're a doll by Andrew Maxwell October 31, 2003