Hey there. I figured this might be easier to chat with you instead of comments on my book chapter.
Like I said, the illness my OC had in my Diabolik Lovers fanfic is completely fictional, but as of yesterday I’ve dubbed it Sanguinare Privation.
Usually, vampires would have venom in their fangs, so taking that idea, I basically made it to where some people are more sensitive to a vampire’s bite, such as Risa. Symptoms often start as some kind of flu-like symptoms, such as fever, aches, fatigue. Over time, the body will literally start to turn on itself, the white blood cells will start dying and the disease will start to poison the blood, causing the body to reject its own blood. This often will lead to vomiting, lack of appetite, relapses of fevers, etc. By this point, the body will start to physically show that it is ill, such as losing weight fast, glassy eyes, pale skin. As the disease progresses, it will start to turn the blood black and the skin will be come ghostly white showing the veins in the body that are black.
In my mind, the illness was terminal as human medicine could not fight against it, but they could provide antibiotics to slow it down. Ultimately, Risa was by all right supposed to die but she was given vampire blood by mouth and that finally changed her into a vampire, saving her life.