Final answer:
Based on the given information, it is not clear why Stevie is perturbed with David.
Step-by-step explanation:
Based on the given information, it is not clear why Stevie is perturbed with David. The provided texts do not explicitly mention any interaction or specific event between Stevie and David that would cause perturbation. Therefore, without further context, it is difficult to determine the exact reason for Stevie's perturbation towards David.