Mr. Tang first appears in this episode. He is part of a running gag with all the parents, whom break down their child's bedroom door with a battering ram while saying "I'm respecting your privacy by knocking but coming in anyway". He then gleefully hands the phone to Trixie.
When Timmy Turner arrives at the Tang Mansion to stop a killer plant he had given to Trixie earlier from eating her, Mr. Tang answers the door. Even though it is late at night, Timmy is dressed oddly and carrying sharp objects, and has a crazed look in his eyes, Mr. Tang thinks none of it and politely lets Timmy into his house to see Trixie.