Scruff Ruffman is Ruff's identical but evil twin brother. He is distinguished from Ruff by five-o'clock shadow (dark hair that appears on a man's face after shaving). He serves time in Poodle Island Prison. Although Scruff and Ruff respected each other when they were kids, they were actually rivals.

He steals artwork in "Scruff Ruffman at Large!". Ruff and Blossom later find him in Mexico in the episode. In this episode, Scruff is revealed to be an expert trapeze artist, but he decided to use the trapeze for evil.  

In "The People vs. Grandma Ruffman," Grandma Ruffman sends a cake to Scruff in jail and is accused of trying to break him out. She is declared not guilty, as the real perpetrator was Scruff's girlfriend Petunia Fidolopoulous.  

Scruff steals the Grand Prize in the Season 2 Finale. Blossom disguised herself as him, met Lester Googe, and saved the prize.  

He appears in Season 3 in "The Old Switcheroo", where he plays Ruff in a hockey tournament. He also appears in the Season 3 Finale. At the end of the episode, he steals all of Ruff's stuff except his pants (stolen by Spot Spotnik). However, Ruff gets his stuff back in "Season 4 is Cancelled."  

In "Season 4 is Cancelled," Ruff is mistaken for Scruff and is put in his jail cell. Ruff finds pictures of the brothers as young children. He then finds notes written by Scruff saying that Scruff needs to "hit all the banks hard and win glory for the Ruffmans." Ruff mistakenly thinks that Scruff is going to do something bad and plans to stop him, It is revealed that he stole Ruff's stuff so he could pay for luge lessons to remove a curse from the Ruffman ancestry. He and Ruff came in last place in the luge race, but they made history as the first canine luge team.  

In "How to Really Train Your Dog," he is seen wanting to obtain the Helmet of Victory and misinterpreting "loser" for "luger" as told by Glen, Ruff's nephew. Grandma Ruffman then tells Scruff to leave Glen alone.  

In Season 5, he appears in "That Sculpture Isn't Yours, It's Mime" when he and Grandma beat Ruff and Blossom in charades, but Ruff and Blossom beat them in a rematch.