Isaac stuck close, all but walking on the Alpha's heels in his attempt. He couldn't hear anyone, could't detect an approach, but there wasn't a chance in hell that he was taking the risk that all of Derek's efforts were in vain because he got himself killed slipping up.

He lets that information sink in, watching Derek and taking him in; the scent on his skin, the sound of his heart beat, everything. But the feel of home, of pack, it was enough that he could feel an exhaustion setting in.

"Thank you."

And he nods and ducks out the doorway.