With this mod installed, you'll start to see Frost Giants spawn in the colder parts of Skyrim. They're similar to the giants you'll encounter during the Dawnguard DLC but they aren't tied to any specific quest.
You probably won't find one of these creatures walking around on the main road. Instead, you'll probably find them lurking about in remote areas like mountain tops, beaches, and islands.
Most of the Frost Giants you'll encounter will be on their own. That said, we've seen some in camps and we've seen some with companions. Bears and wolves are common pets.
Note that these creatures are not leveled and lower level players should avoid them.