Derek really did feel awful. He didn't want to hurt her, he really didn't. He didn't want to do anything that would cause her any distress, but this whole thing was rather high on the scale of stressful situations. He glanced down at her bump again when Erica touched it, and of course there was that to consider.
"Ask Meredith. Whatever she says I'll go and find. I'll go into town and find it, wherever I need to go," Derek nodded his head. "And if that doesn't work, if it doesn't work then it'll be fine, I'll be there, I'll be there the whole way through, Erica-" He stepped forward, taking her gently by the shoulders to focus her attention on him. "I know that running away is easy. And it's not a bad thing. I know what you want to do, to keep away, and if this were a week ago then maybe I'd think you could do it, get far enough away to not be able to come back as a wolf. But even that-"
Derek sighed, lifting a hand to push her hair away from her face. "Very last resort Faith will tranquilise you. Last, last resort. I won't go anywhere. I promise I won't go anywhere. I'll chain you up myself. I'll stay in there with you. I won't go anywhere, Erica. You're my responsibility. Both of you." The baby might not have been his, nor even anyone in his pack, but Erica was Derek's beta, and that was what mattered to him.