Rolly is known for his excessively large appetite. He can be gentle and carefree at times, but after his family, food may be his true love. Even after just eating, Rolly can be seen asking for food and the only one of the puppies constantly starving. He may even put his life in jeopardy for a decent meal every now and then.
Rolly is one of Pongo and Perdita's fifteen puppies. He is the heaviest of the puppies and is constantly hungry. He is usually heard asking his parents for food, even after being rescued from Jasper and Horace Badun by his parents. When the Dalmatians attempt to disguise themselves by rolling in soot to look like Labradors, Pongo quickly sends Rolly back, as Rolly was only half covered. At the end when the puppies returned home, Rolly was seen yet again asking his mother for dinner.
Rolly is one of the three main puppies focused on in the series; the other two being Lucky and Cadpig. Like his original film appearance, his gluttonous appetite is one of his main flaws, and his desire for food has been known to cause problems for himself and also his siblings. However, he is said to have the strongest sense of smell out of the other Dalmatians. He is also shown to be very loyal and helpful, but takes great offense to being called "fat" and would strongly deny it. Additionally, Rolly often hesitates when it comes to going on adventures with his siblings, and prefers to remain out of conflicts even if they could really use his assistance.
Rolly has adapted perfectly to his life with the other 84 puppies and retains his incredible appetite as seen when he tries to eat two bowls of Kanine Krunches. Later on, Rolly and his siblings are kidnapped, and when they are rescued by Patch, Rolly acts as his second-in-command. They use a tram to escape Cruella, but Rolly begins slipping out and gets captured by Cruella herself. Patch's quick thinking enables him to rescue his brother, and they all return home safely.
Being the most overweight of the puppies, Rolly's cameos on House of Mouse were not hard to spot. In "Pluto Saves the Day", he and Patch join an all-dog band singing "Everybody Wants to Be a Woof", parodying the song "Everybody Wants to Be a Cat" from The Aristocats. Later in that same episode, Rolly is seen with the other Pet Shop Dogs fighting off Pete (who is disguised as Snow White) and then chasing him out along with the rest of the dogs and Pluto. Like in 101 Dalmatians: The Series, Rolly sports a blue collar instead of red.
Rolly makes an appearance at the Midship Detective Agency attraction in the game, "Case of the Missing Puppies." As the detectives look around the Disney Fantasy cruise ship with Pongo, Roger and Mickey, they find Rolly with his stomach stuck in one of the vent shafts. He is able to get free from the vent, then notices the detectives and licks the screen, with them closer to finding the other Dalmatians on the ship.
- As with all the males in the original 15 Dalmatian puppies, Rolly wears a red collar in the original film and in 101 Dalmatians II: Patch's London Adventure. In the TV series, however, he wears a blue collar like the female pups. He also wears the blue collar in his cameos on House of Mouse.
- His name is most likely a reference to Disney imagineer, Rolly Crump.