Don't walk into the enemy's den
Years pass.
Xi Zirui survives by doing jobs for humans. The kind of jobs no one else will do, at least not at the prices he charges.
Whenever someone wants to get rid of someone they know how to find him -- and that Xi Zirui never says no to a job.
Whether it's children, women, entire families; he'll wipe everyone out.
He has no mercy for humans because they wouldn't have any mercy for him.
The only human he has ever loved is long gone, and no one showed her mercy either. He imagines the face of the haughty cultivator over the ones of every person he kills.
Not for any sentimental reasons, not because it makes him feel better about the task at hand, but because he wants to keep his face fresh in his mind.
He hasn't forgotten the promise he made in front of Tuya's grave.
Years pass, he grows from a scrawny child into a gangly teenager, and then he starts getting other kinds of proposals.