It looks like a routine check to me. The black top probably is concerned that his gorgeous cock is not as big and thick as it used to be so the doctor is making a very deep study of his massive sexual organ which included worshiping, pleasing sucking and fucking that black cock. Obviously he as take sample of the jizz by swallowing every drop with his mouth. The final result is that black cock is just fine but the doctor have to make home visits every night to repeat the same treatment to his new black daddy.