Aziraphale was shocked. He was just kissed by a demon, his demon, Crowley, and by God did he want more. He just couldn't accept. He subconsciously stuttered out a small "do it again." Under his breath, but it was clear the demon didn't notice before he placed his hands on his lips. The angel was shaking, he realized. He didn't want to choose Heaven. But he had to, to protect Crowley.

"I forgive you." Instead, he managed, after stumbling. Even if the demon didn't do anything wrong.