How should I answer to homecoming?

On my doorstep he left a huge rock ,that I can even push because it's so heavy, that he spray painted NO on, and then a rock the size of my hand that says YES on it. The poster said "It would be a rocky road if you didn't go to homecoming with me" and I'm supposed to return the rock that I'm going to say (yes or no). I'm saying yes, and I want to stay with the rock theme. Any ideas?