Had this specific concept for Illustrious. So here you go!

Strength: 0.7-1.0

Prompts that worked for me:

the image shows one woman and one man. the girl performs oral sex on the mans large penis. the penis of the man bulges very visibly one of her cheeks. her tongue is shown under his penis. only the lower body of the man is visible. his upper body is out of frame and his face not visible.   the photograph depicts a explicit scene of a sexual act. a woman is kneeling and performing oral sex on a man. she has her tongue out, licking the head of the man's erect, circumcised penis. the mans lower torso and genitals are visible. his head and face is not visible and not in frame. mans hand is on her head. she is drooling saliva and semen. 

She is looking at the camera.