Stuart G. Yates 
Sallowed Blood [EPUB ebook] 

In the dark corners of a castle deep in the Alps, a secret awaits Daniel Stone. After inheriting the castle from his grandmother, Daniel and his father travel to Bavaria.
They soon notice a dark presence in the old stronghold: strange noises echo from the depths beneath the castle, and someone or something seems to be following their every move.
After things spiral out of control, Daniel and his father receive unexpected help from an old relative, who tells them of the dark secrets the castle holds. But even with the three of them, will they be able to discover the centuries-old mystery that lies buried, or will darkness claim them all?