Original post here. Art is clearly by Dorian Cleavenger, who has a site here. Original text (not mine, but a good example of what an image can inspire in someone):

familyfant:

Every night she performed the ritual, without exception. 

She would open the basement door, step through into the darkness where she knew with certainty that something was lurking, and willingly let it claim her. She would be nude every time – to make the monster in the darkness want her instead of killing her. The sight of her naked body would entice the monster and at that point it would forget the hunger that tormented it. She would be bred with instead of being eaten.

The consummation would be rough and prolonged. The beasts many tentacles will coil around her and pull her legs apart. It would force her to bend over and it would mount her. Its many cocks would force their way inside her pussy and ass. As soon as one ejaculates, another takes its place. This would go on for hours. 

She would orgasm repeatedly. At first she hated it but after years of monstrous sex, she would come to enjoy it immensely. She now recognizes all of the beast’s many cocks by feel alone. They are greatly varied in size and shape and she has names for all of them. Merry-Pete is recognizable by the amount of cum it produces. The Hammer is a cock with a very wide head that’s painful as it enters but feels blissful inside her. Gremlin is a cock that exclusively prefers her anus, going deep inside her. It squirms deep inside her colon until 5 feet of it completely occupies her large intestine. Devil-Jack is one that has bumps covering it and feels much hotter than the others. There is one that is thin and tapered that likes to play with her clit, one that’s long and divides into 4 cocks at the tip – that one likes to touch her breasts and face, sometimes she even takes it in her mouth. One has an eye at the tip that just examines and scrutinizes her genitals. One that she likes is a cock that is short but balloons into a large ball inside. There’s one that’s very large and wide. It’s massive. That one scares her. Fortunately it rarely takes part in the activities. From time to time it has her play with its large scrotum and 14 testicles. The beast has 2 sets of pincers on either side of the mouth, which it uses to spread and stretch her labia as its tongue repeatedly penetrates her. Pinched, stretched and penetrated simultaneously. It’s her favorite. 

Eventually every night ends with her weak legs struggling to get her up, then she squats over the beast’s mouth and empties her vagina and anus of all the semen inside her into the beast’s mouth. Her anus alone produces over a gallon of semen that’s been pumped up inside her over hours. If she urinates then the creature drinks it with relish. She goes back up the stairs and leaves for now.

The beast used to be a beautiful young man until a hellish curse was put upon him. He angered an old sorcerer who unbeknownst to him was controlled by a powerful demon. The demon used all of its might to turn the young man into the most vilest being imaginable. A being whose sole ambition is raping and eating humans. 

She managed to lure the creature into her basement where she trapped him. To stop it from escaping, she offered herself to it, to let it violate her. She knew it would want her. Once, before he became a ghoulish beast, he had snuck up to her from behind and hugged her. His hands had touched her, squeezed her breasts, squeezed her ass. They had gone up her dress and caressed her between her legs. He told her he loved her and couldn’t stop thinking about her. She felt desire and lust try to overtake her but she knew she had to stop before they went too far. She told him it was forbidden and he left. Now the beast would never touch her gently, would never tell her it loved her. Now it knows only rough violence and force and never will it caress her gently. But she couldn’t let it escape and eventually be killed by the other people. She no longer had her dear brother, but she had the beast and over time she even came to love it. 

Eventually she realized that the beast’s numerous cocks were all manifestations of her brother’s fantasies about her. She knew the beast wasn’t miserable but happy. To have his sister and her body was her brother’s greatest desire. And now it was hers as well.