Len very nearly bulks at the touch, not used to anyone laying a hand on him but his father, and not in as gentle a fashion as this. He's somewhat startled, distracted by the thought as he glances at the hand around his wrist. It's large and warm and despite the clawed grip, it's light and careful. It's surprising to say the least, but he manages to shake himself of it, long tail flicking with slight agitation. It's a knee-jerk response to being touched, or caught off-guard.

He'll quietly focus his attention to the collar though, a flick of deft fingers and a mutter in magical tongue and the spell fades. He then pulls out his lock-picking tools to get the heavy thing off of the half-dragon's throat, tossing it to the ground. An uttered word and he'll expel cold, white-blue energy from his fingertips to freeze the thing solid. He slams his heel into it to shatter the collar completely before nodding his head towards their escape.

"Lets go." Just like that he turns on his heel and slips off through the dark, almost slithering through the element as if he was born for it.