I thought at first, she standing their in this fire lit room a fire burning behind her, she must be evil. She looks like the devil in this scene.
But this is not about Christianity, it is about the Lumon religion! She is the fallen arch angel of Lumon! She is not the antichrist, she is the anti-kier!

Lumon is all about the cold. Cold colours everywhere, the iceberg picture in Milchicks office, the home town of Cobel (home town of Lumon as well?), Cold Harbour, ...
But there is Cobel standing in very warm light with a fire cracking behind her. She is no longer a soldier for Lumon. She is the anti-Kier now! She wants to burn this company to the ground now!