An Aesop: You shouldn't have to lie in order to spare your loved one's feelings. If there's something about them that's bothering you, they'll understand if you're forward about it.
Brutal Honesty: The moral of the story. Sagwa was afraid of admitting to her grandfather that she didn't want to hear his stories because of his bad breath from the Hundred-Year Tofu. Later, she finally tells him that she avoided him for his bad breath, not because she didn't want to hear his stories.
Jerkass Ball: The Magistrate isn't very understanding with Cook for not having his Hundred-Year Tofu ready. And he doesn't even know Cook shared some with Sagwa's grandfather, much less an excuse for losing his temper over not having enough of it.
You Need a Breath Mint: With an episode title like "Stinky Tofu", it doesn't take a genius to guess why Sagwa's Grandfather's breath smells so bad.