In his first appearance, he is shown to be very grumpy and angry, as if mad about being kept as a pet and doesn't believe the master is wonderful; possibly because of his past experience with humans who screamed at him, threw things at him and called the exterminator on him. He's rude to pretty much everyone, but as the story goes on Ratso's heart begins to warm up to the others, especially when Radio gives up his live to give the old computer Wittingstine the spark he needs to help them save the animals. Once they managed to reach the truck Ratso pulls Masie the cat out from under some boxes and cries for her, believing her to be dead but she wakes up and calls Ratso a hero, which he responds by embarrassingly toys with his tail and smiles. The next morning Masie allows Ratso to be the first thing her babies see and he is happy to play with them. Later when he hears that the others have homes except him he sadly sulks but he is overjoyed that Chris says that he is coming with them, stating that she thinks he's 'kinda cute' and is as happy as the appliances when the couple revive Radio with his rare tube. In the end he leaves for his new home with Toaster and his friends while waving good bye to the other animals and singing 'Hang in there Kid.'
In his second appearance, he is shown to be very kind and helpful to Toaster and the other appliances. He stays behind and stands watch while Toaster and his friends go on a mission to rescue Robbie, who is referred to as the "Little Master" by the appliances.
- Ratso bears some resemblance to The Rat from Lady and the Tramp, but unlike Ratso, he's an antagonist.
- He is the first Disney rat character who is a protagonist, the second being Remy from Ratatouille.
|The Brave Little Toaster|
Songs: April Showers | Tutti Frutti | City of Light | Mammy | It's a 'B' Movie | Cutting Edge | Worthless | Bread and Butter | I See a New You | Floating | Fight Right | Home Again | I'm Into Something Good | Remember That Day | Cocktails for Two | Super Highway | Chomp and Munch | Hang In There, Kid