A crude way of expressing love through snide interpretations of the other partner being a round object of lust. Usually meant in the nice way, but in some cases, if you are a round object, this could mean that she is calling you overweight and need to stop eating so much.
(Pumpkins are fun to carve, this could also mean that she wants to fill your holes with knife like objects and carve you the way she wants you. Being scared is advised.)
I accept that you're round, but I'm going to carve you the way I want you so I can show you to my parents. I love you pumpkin