Lifty and Shifty are a pair of green raccoons appearing in the Happy Tree Friends series. To separate the twins apart, Shifty wears a fedora hat like Henry Jones, but it's greenish-white -- they are also kleptomaniacs, meaning they will steal anything that isn't nailed down (heck, even the stuff that is nailed down) -- they have no qualms about what they steal or who from, they almost always end up being horribly killed as a result of their own misdeeds or simply because of bad luck.
Lifty and Shifty are some of the few main cast that are continually portrayed in an antagonistic role and are one of the few Happy Tree Friends that can act deliberately malicious towards others.
Unlike the psychotic Flippy or superhuman Splendid, neither Lifty nor Shifty seem to have remorse over what they do though, unlike Flippy, they almost always receive fatal retribution (while Flippy and Splendid are famous for their resilience to death -- though they are far from immune to it).
However, despite their nature, they show their good side. When the rest of the Happy Tree Friends are stranded on a island surrounded by water, Lifty and Shifty help by taking out an inflatable lifeboat.
Though they still almost always fail, Lifty and Shifty are shown to be willing to go to great lengths to steal what they're after. A notable example being that in Junk in the Trunk, they want to steal Lumpy's elephant but can't move it to get it in their van. Instead they: unload all the other stolen animals (caged), completely dismantle their van, reassemble the van around the elephant to full working condition, and reload all of the other stolen pets.
However, in Meat Me For Lunch and Buns of Steal, they were shown to be very poor and starving showing that they may steal because they need to, not out of malice or kleptomania.