Ruby

"The seer's fortune already has a new owner." 

The surprised faces of the four were priceless. No one could maintain their composure as Ryan so casually declared that before the seer's death, he had made him change his will. 

His reason was that there were too many things to manage, and he didn't have the time nor the desire to do so.

He also made it clear that he wouldn't engage in any conversation regarding selling the guild to the government if that was their purpose for paying a visit today. 

Ryan hadn't anticipated the seer's death. He thought about the reason and reached one conclusion: the parasite. 

It seemed that since his physical health started deteriorating, the parasite was instigated to kill him along with its master. That was the type of parasite 'the seer' used on Hiro, but it was never mentioned in the novel.