Han Sen had received many answers from Human King. When he left Blood Legion, he still had a few things that had yet to be cleared up.
Just as Human King said, he did not ask Han Sen to do anything for him. It seemed as if he was just convincing him not to expose the identity of humans in the universe.
Human King also gave him Blood-Pulse Sutra's final part. He told him that if he was willing to, all he had to do was practice the final part for his blood to turn into blue blood. Although this method was not as pure as passing it through generations, it would still give Han Sen blueblood power.
The price to pay was that Han Sen would lose all the geno arts he currently had. He would not even be able to make use of beast souls. All he would be able to use was blueblood power.
Human King did not force Han Sen to do that. It was a decision that had to be made by Han Sen.
