Knock on his door. When he answers, ask if it's ok to take a dump at his place because your crapper is busted. When he reluctantly says ok, thank him and start to walk away. When he then asks where you are going, kindly inform him that you already did your business and point to the steamy pile of last nights chili cookoff, post digestion, on his hood.
Smile and say thank you, you appreciate his generosity.
