Going back to the idea of Vampire Jon and Humanish Elias.

Elias keeping Jon like an exotic pet, he should be dangerous but Elias has basically instilled learned helplessness into him. Elias keeping him collared and leashed, showing his off as a pretty trophy. Showing how well trained he is like a tiger in a circus, baring his fangs only when told.

Elias rewarding Jon for his good behavior letting him hump his leg like a dog. He keeps him half-starved so Jon is desperate for him, letting Elias do whatever he wants as long as he can feed. Elias keeping him in his lap, making him warm his cock, as he slowly drip feeds blood to Jon, making him feel desperate. Telling him he’s such a good boy look how well trained he is to wait for his food.

Jon being severely punished when he looses control and bites when Elias doesn’t tell him too. Jon whimpering and crying and Elias telling him it’s for his own good, he’s a monster after all.

Jon could leave at any moment, but he chooses to stay. Chooses to let Elias keep him under control, to be a good pet.