|Job||Newspaper sports reporter|
|Cartoon debut||"Bitzi's Beau"|
Harry Mills is a sports writer, photographer, and journalist for the Elwood City Times. He and Buster's mother Bitzi both encountered each other in "Bitzi's Beau," and became a dating couple. At first, Buster thought he might be an alien from outer space, but turned out to be a very nice man, and that he works where Bitzi works. He and Bitzi later broke up in "Bitzi's Break-up", but stayed friends.
At first, Buster thought that Harry was an alien. However, Buster thought differently when he told a joke when he arrived for dinner at Buster and Bitzi's condo. Once again he thought Harry was an alien because he accidentally stepped on Buster's toy that "detects aliens".
While eating dinner at their condo, he was constantly telling jokes, which caused Buster to laugh and almost spit out milk. His tie accidentally got soaked in crab chowder, and then all three of them laughed.
Harry brought dessert to the dinner, and Buster thought that it was a trick involving Harry being an alien. He was disproven when he opened the box and found out it was nothing more than a Boston cream pie.
While Harry was leaving, Buster and Harry shook hands. He remarks that "Even if he is an alien, he's a nice one". Buster then sees Harry and his mother laughing with each other. He gets worried that Bitzi won't spend enough time with him because of Harry. Bitzi promises that Buster will always be the most important part of her life.
Harry brings Buster to an Elwood City Otters hockey game along with Bitzi. Harry and Buster turned out to be good friends.
Harry Mills is a rabbit depicted with a beige complexion and clumps of hair, and wears a red and brown suit with a tie and tan shoes.
- 505b. "You Are Arthur" (his name is on the sign-up sheet)
- 508b. "Bitzi's Beau"
- 801b. "Bitzi's Break-up"
- 909b. "Buster the Myth Maker"
- 1006a. "The Curse of the Grebes"
- 1101a "Swept Away" (mentioned)
- 1209b. "Do You Believe in Magic?" (mentioned)
- 1607a. "Baseball Blues"
- 1703a. "Molina's Mulligan"
- When Someone You Know Has Cancer (2014 edition)