Derek gave Stiles another near smile, his eyes soft as he followed the line from Stiles' mouth to his cock. "It's not weird," he promised, his hand lightly petting the teenager's hair. "It's exactly how you should feel," he praised. "It's a good sign," he added, softer. There were things he could teach--techniques, skills--but he couldn't teach Stiles to enjoy it. Not like that, anyway. "Just go slow," he repeated. "Take your time. Hold it as deep as you can, as long as you can, then pull back, take a breath, and try again."