Haha, when I saw a different version with the dog, the guy was like "i feel bad about smoking, but i'd feel less bad if you smoke with me" and the dog was like "no thanks" and walked off and raised his flag. Lol, being lit, my brain played the version that it thought would be funnier for me afterwards, it went something like this:

Pot Smoker (sitting on window): "Hey dog, you wanna hit this?"

Dog: "No thanks."

Pot Smoker: "HOLY FUCKING SHIT A TALKING DOG!!!!!!!!"
*falls off window*

*scene fades to black*
(in big white, centered letters): "Marijuana: It's the shit!"