He is preparing her.

He grabbed through from behind under her thighs, massaging her clitty intensively and pulled back his then soaking wet fingertips. He was spreading her buttocks. His wet fingertips came close to Mary´s backdoor.

The soaking wet fingertips reached her asshole, Mary shivered and was stiffening. "Relax ... loosen up... don´t cramp!". Mary was obviously not feeling comfortable. A shiver was running down her spine. Despite of this she didn´t stop him.