I love vampires au jonelias because their canonical relationship already fits the tropes so well. you have Jon being being turned into a monster, the hunger that causes him to harm others, the guilt that comes with that etc. you can also the vampire diaries route (I don’t know if it was done anywhere else) and have Jon develop stronger feelings for Elias/be more susceptible to his commands because he was the one to turn Jon
totally not because I just think it would be very sexy for Jon to feed from Elias. sitting on his lap as Jon bites his neck, or Elias holding him, pushing his wrist into Jon’s face