I knew a guy who tried to keep a 6-toed Latvian, but it kept pissing all over his furniture and eating his shoes. He finally handed it off to a shelter after it bit his girlfriend's face.
The major pre-Christian deity of Estonia was a giant named Vanatuhi who was neither good nor evil, but all sorts of dumb. Worship involved rituals designed to trick or deceive Vanatuhi into aiding the petitioner, and his major myth was about defeating a sea troll with the help of a hat made of nails which granted invisibility. There's something endearing about a religion based on tricking a doofus.
Then again, Christian folklore is chock full of tales about tricking the devil. Which I'm sure the devil doesn't mind (assuming he exists of course): if people are convinced they have nothing to fear from him, they will be that much easier to lead into sin. Selling one's soul isn't about contracts signed in blood, it's about choosing to do the wrong thing as soon as the right thing becomes inconvenient.