Prompt: Write a short story about a man who discovers a magical portal

Jeff was a typical man, until one day when he discovered a portal to another world. He stepped through and found himself in a place full of fantastical creatures. Jeff was quickly captured by the creatures and was forced to work for them. He was miserable, but he was also able to explore the other world and learn about its history. One day, he escaped and returned to his own world, where he told everyone about his adventure.