Once Human, Now a Parasite

Arthur, a Rich businessman was kidnapped and tortured for months by men his wife hired. After months of this hell, he was given a second chance, a new life in a different world and, of course, Arthur would rather start a new life than stay and continue to be tortured, so he accepted the deal that was proposed by a mysterious individual, but when he finally was reincarnated, Arthur discovered he was a..... parasite?