"I understand your skepticism, and I don't blame you for being cautious. I'm clearly not one of those eye-themed monstrosities your companion mentioned, and the fact I was put in a cage proves that my danger to you is minimal. However, if you're out...exploring, having another ally in your group could increase your chances of survival. All I'm asking for is an opportunity to demonstrate my trustworthiness."
Pausing briefly, he continues to address their earlier questions directly, "To answer your questions: I was transformed by a magic mishap, courtesy of a goblin witch doctor, while I was in the midst of battling goblins."