The Robot Pet is a character that appeared in the episode Kirby's Pet Peeve as a temporary playmate of Kirby's. While not a monster in the true sense, this cute robot puppy was a product of Nightmare Enterprises Toys. Tiff got it at Gengu's toy store as a playmate for Kirby, since he didn't have anyone his size to play with. It has a wide range of abilities, many of them dangerous like knife-like claws and the ability to electrocute anyone who touches it.
At first, Kirby was afraid of it, but they became good friends. However, King Dedede was interested in the dog and wanted to play with it, so he tried many times to capture it. Meanwhile, Tiff discovered its true origins and tried chasing it away to protect Kirby. The dog was set to self-destruct when Kirby was near, but it remembered how Kirby had helped it, and jumped away at the last moment. Dedede managed to catch it with his net, but the dog self-destructed on his and Escargoon's motorboat, landing them right in the water. In the end, Tiff felt bad but at the same time was glad to know that Kirby and the dog were friends even to the end, and even Gengu knew that nothing could replace the friend that Kirby had lost.
The Robot Pet is a small, light orange, mechanical toy dog with purple ears and a tail, and eyes similar to Kirby's, which it wears a transparent red visor over. The dog has many hidden features, like a drill, knife-like claws, and electric charges, and even a time bomb hidden inside.
It is able to use knife-like claws to slice pineapples and use a drill in its mouth to cut a hole in it, producing pineapple juice. It is also able to perform electric shocks when in crisis, such as being stolen. Finally, as its true form, it can activate a time bomb and is able to hover above water.
Throughout the episode, it seems that Kirby refers to the robot dog as "Smile."
- It seems to be based on the Poo-Chi robot dog toy that was popular at the time, due to their similar appearances.