Castiel was helpless here, not knowing what to do and how to react. Up until now, all the time he spent with Meg was done so in the comfort of his apartment. Comfort being a relative term, because he still hadn't accepted that it was truly his and he was meant to use it for the duration of the time he was in Oakdell. Being in Meg's domain, it was enough to continue to throw him off balance because she knew the layout of her home a lot better than he did. She knew the ways to corner him, where to do so and to use their close proximity against him. Like she was doing right now.
When she started at his coat, he shook his head a bit, "No, it's actually quite comfortable. I'm not warm at all..." He tried to reason, although he was feeling just a bit uncomfortable now. It wasn't to do with his coat, however. Meg had a way of getting him to react in the way he didn't intend on doing so when he originally came here. And without the security of his coat, he now had nothing to wrap around himself to use as that barrier between them.
"Do you require my coat because you're cold?" He was looking at her again, at her current state of undress. It was an awkward response, made more awkward by the fact that he still thought of kissing her and wanted to, but there was also a line they had not yet crossed. Each kiss had been on her terms and he reciprocated. He had yet to initiate anything between them and he wasn't sure of why, other than being overwhelmed with trying to figure out how to make due with his new human life and figure out what the feelings he had for her were. To go from there.