Arthur possesses a talent that even the true children of the family don't have. It is a talent that he can never possess.
If he had half as much talent as Arthur, his situation would be better. Unfortunately, he wasn't so lucky.
Since it wasn't his fate to be talented and accepted into a sect, he will have to settle for second best.
Second best had usually been bullying commoners and running the criminal world from behind the scenes. But today he has the opportunity to enjoy something rare. He has the opportunity to kill a genius.
The killing of geniuses is a rare treat. But Arthur's genius is something he can only encounter probably once in his life. So killing such a genius is a special treat that he might never enjoy again.
Just thinking about it made him curl his lips in a grin. Then he called back the waiters and resumed enjoying his lunch.
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