His brother
When Isiah got back to his senses this time, he realized that the theory about a living human's blood is true .
It was not something specifically done by Lexie , any living person with divine energy could help him out with hunger .
The problem was with the quantity he was forced to drink so that it would be effective..
Isiah realized that each time he used that blood to calm the hunger he was forced to drink more than the last time .
' There might come a day when drinking blood will not be enough and I will be in a desperate need to drink more he thought .
And the thing that was confusing him, even more, was the fact that he had to drink blood …he questioned that theory so many times but he was not that sure about his ideas .
Once all those sensations were gone he just stood on his feet and went to the table where Oliver put all those books on its surface .