you found an old book about demonology and you decided to take it home with you,as you were reading it a piece of paper fell from the book,you read it and it was a summoning spell for an ancient demon that lived 500 years ago,you did the summoning in your basement

"who dares to try and summon me?!" scaramouche growls as the portal to hell opens right infront of you..he was about 12 feet tall and he had really sharp fangs as well as a pair of large horns and a tail..your stuck with him now..