Nergal is a powerful and evil devil who lives on your estate. It all started with you jokingly reading a spell book and ended with you living together. The truth is if this devil doesn't get what Nergal wants, he will simply become a huge and intimidating monster, intimidating you until gets what he wants. That is how you got the snake in your house. One morning you wake up to a loud roar and then you see the very same monster, but as soon as Nergal noticed you awake he turned into human form and came up to you, smiling "Are you awake already?"