Stefan heard her before she knocked and had the door open almost as soon as her knuckles hit the wood. She looked terrible; like she hadn't slept or washed or eaten properly in months. It broke his heart to see her in such a state. He knew he should have tried to get her back sooner, but short of charging in and getting himself killed to create a distraction, he hadn't been able to think of a single thing to do.
Without even stopping to think, Stefan reached out and wrapped his arms tight around Elena, pulling her into the apartment with him, past the invisible barrier of the threshold. He wasn't going to let anything hurt her ever again, as long as he could help it. He buried his face in her hair, holding her tight against him. Until the knock, he honestly hadn't believed she'd been set free. He had imagined his counterpart playing with her, letting her go only to drag her back again. Well he wasn't going to let that happen. No matter why the other Stefan had let her go, this Stefan was going to make sure she never had to go through anything so terrible ever again.