Okay here is my dilemma, I'm writing a story about someone who has a very rare illness and even rarer bloodgroup, and for now can only stay alive through blood transfusions. His condition is deteriorating and his body no longer accepts regular bloodpacks for a transfusion. Only a direct transfusion seems to help him (so person to person). ( I know it seems maybe a little farfetched but bare with me) In my mind I have made up a good and plausible reason for all this, but herein lies my problem. I'm no doctor, nor specialist on the subject of blood, although I did read through about a dozen sites on this particular topic. I know I can describe it, but I can't scientifically back it up, since it's probably more fantasy than thruth... My question is how important is it to stay true to real life, or can I play around with science a little? And if so, how technically do I need to explain? Can I be a little vague about it, or do I need to back it up...? Or should I just forget about it all, and stick to the rules of science? Anyone still with me?