Skyrim Special Edition's Creation Club is having a sale, and as part of that sale you can get your own pet Nix-Hound for free. It'll cost your in-game character 400 gold and a trip to Solstheim, but you the player won't need to spend any real money on Creation Club points to get it.
The Nix-Hound is a bug-eyed dog creature you might remember from Morrowind. This add-on not only lets you pick up one of the wall-eyed beasts as a pet (with its own inventory to carry your burdens), but also adds them as roaming monsters across the isle of Solstheim, which could use the variety.
You'll have to access the Creation Club via the main menu to find the Nix-Hound add-on. If you're after free mods then here's our list of the best mods for Skyrim Special Edition, and for vanilla Skyrim.