If she was lying on the ground, he would have easier access to her face by standing at her head and it would be a regular “B” looking down at her.
If she was lying on her back, and he was on his knees facing her, maybe holding her head between his knees, holding her right arm across her body to control her and turn her head, the B would be upside down and at a slight angle (due to her turned head) - which it is.