Billy had never imagined that the Kamor family could give rise to a chosen one like Brian.
For him, who regarded the family as an obsession, this was probably the best news in the world.
Billy felt he could die without any regrets.
...
Brian interrupted Billy's self-indulgence, "Sorry, the task of revitalizing the Kamor family is Fooly's, I have my own surname, my full name is Brian Lee. I will have my own family, my own descendants."
He didn't really have to say this, but seeing Billy so excited, he was somewhat annoyed.
Billy had his obsession.
But when the other party imposed his obsession on Brian, trying to control his life, it became difficult for them to continue to be close like normal relatives.
Billy didn't care at all about what Brian said.