Evil against Evi

The King of the Underworld, Arn Milford, was killed by a glorified hero who wasn't even properly trained. Arn just let it happen.
Opening his eyes after a couple of hundred years, he realized that he was far from his castle, Kashan told him that he had revived it and then offered a contract. Their goal was to kill the heroes until Arn was fully strengthened.
But why the hell does another villain change his goal and try to kill that hero not only for his actions, but also because he fell in love with Arn? And in general, get these two away from him before the heroine finally floods him with her tears and tantrums!!!
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