After Squidward reads SpongeBob's diary, Quincy comes to repossess Squidward's house.
Relationship with SpongeBob
He seems to dislike SpongeBob. In "The Card," he seems to have dealt with SpongeBob before this episode and disliked him from that. In "Model Sponge," Quincy does not like that SpongeBob makes a "Krabby Patty" out of money. He then fires SpongeBob.
However, in "Little Yellow Book," he somewhat defends SpongeBob after Squidward reads his diary.
Relationship with Squidward
Quincy only interacted with Squidward once, in "Little Yellow Book." Quincy repossessed Squidward after reading SpongeBob's diary. He seems to dislike him.
"SpongeBob, I don't think they give the money directly to Mermaid Man and Barnacle Boy."
"Squidward Tentacles,by reading another person's diary , you have violated your loan, we are repossessing your house."