Golem Master Master

Harry was an ordinary undergraduate student at Oxford University in Britain, his dream was to graduate, find a suitable job, and then marry his childhood sweetheart, Sally. This was the dream of every university student, a peaceful life, isn't it, but the winds do not like The ships, his girlfriend rejected him, and his parents died as a result of a traffic accident, and he did not have enough money to complete his university studies, so he left the university despite being in his last year.
Life became black in his eyes, no family, no money, no job, no girlfriend.
He was evicted from his home by his uncle, and became homeless.
After all, this was only the beginning of his troubles.
When he was in an alley, he found a wounded man bleeding from every part of his body, it seemed dangerous, but what happened Harry did not expect when he wanted to help him, the mysterious man took a small dagger from his jacket and stabbed Harry's right finger, drops of blood fell on the book which The man was carrying it, and the book flashed in a magical scene and then disappeared.
"We'll meet again, young man, haha."
The man disappeared in a magical scene.
Who is this man ?
What is this flashing book?
And what is the fate of Harry?
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Follow the novel to find out the mystery.