Yikes, Dobby is NOT having it, no matter how much you try to reason with him that you'd be safer at Hogwarts than you'd be here! It's just not an option for you!
Dobby makes a run for it and jumps three steps at the time towards the kitchen. In absolute panic and shock at the Dursleys imminent reaction to seeing such peculiar a creature as Dobby (and the inevitable punishment that will await you) you don't even notice the cake hovering over the guests heads! You jump into view trying to stop this disaster from happening, in retrospect you'll understand that Dobby was too short for them to see and it definitely looked like you're just doing all this by yourself!
Matters not, you know you'll be blamed for it either way.
What a mess!
Well... that's that. Seems like Dobby has gotten what he wanted. You're not feeling particularly fond of the elf at this moment, maybe once you manage to get the bars off your window, maybe then...
Wait, the bars seem to have moved. A car, a flying car of all things, has shimmered into view and a bright freckled face from inside of it. Actually, three of those! Ron and the twins have came to take you away! Let's get the hell out of here! Don't forget to grab Hedwig!!