Jeff saw that the person following him was a short, hobbling old human man (his new mindset found it necessary to qualify the new man as human because of all the non-humans running around) wearing worn grey robes, with a long white beard and a walking stick. His face seemed kindly but also like there was something off about it.
Jeff was perturbed. Perhaps against his better judgement, he turned away and made his way through the crowd (stopping to pick an especially fat and poorly-guarded pocket along the way) and once he reached the old human demanded, "Who are you, and why are you following me? What do you want from me?"
"Excuse me, young man," the older man greeted in a doting tone of voice, ignoring Jeff as though he had never spoken, "I couldn't help but notice that you had picked the pockets of one of my companions, a dwarven fellow." Jeff had indeed robbed a male dwarf in adventurer's attire. "It just so happens that he and I are members of a company on a quest, of sorts, and it just so happens that we could use someone with your... particular talents. Indeed, your skills at stealth and trickery would be a great boon to us. So what do you say, boy? Are you up for an adventure?"
The old Jeff would have jumped at the chance, out of curiosity if nothing else, but the new pickpocket Jeff was different. A life on the street had made him more cautious and more independent, and he shook his head. "I'm not going anywhere with you, old man."
The old man's face darkened, suddenly, filling with a surprising anger that seemed to be equal parts cold contempt and hot rage. "I will give you one more opportunity to give the right answer, and if you do not then I will turn you into the rat you are, you dirty little thief."
Jeff was worried and confused, and asked, "What--" But then everything seemed to change. Everything was perfectly still, except for the wizard, glaring at him. He felt himself dropping--no, shrinking. His clothes swallowed him up as he grew too small for them. His whole body was rearranging. Black fur grew over his body, his face pushed out into a rodent snout, his nails and teeth sharpened, and through the shocking sensation of the transformation Jeff managed to squeak out, "Stop! I'll do it! I'll join!"
"Excellent!" The old man, who was clearly a wizard, snapped his fingers, and everything went back to normal. Jeff swelled back up to his normal size, fur and snout receding, and everyone on the busy street resumed moving like nothing had happened, clearly not having noticed the magical incident. Jeff was left panting in shock, breathing heavily as the wizard beamed a happy grin, seeming the kindly old man again. "Ah, excellent, excellent. Now just come along with me and I will introduce you to my fellow traveling companions. After that, once the necessary arrangements are made, of course, we can be off on our quest!"
The wizard set off down the street, and turned back to shoot a murderous glare at Jeff when he hesitated, bidding the younger man to follow. Clearly it was not something up for debate, so Jeff followed behind the wizard, his mind racing.