When Lin Yuan mentioned gatekeeping, it hit the Dark Demon Ape's sore spot.
Because this Dark Demon Ape's family, for eighteen generations, had been gatekeepers for a supreme being from the Mysterious World.
His father was a gatekeeper, his grandfather was a gatekeeper, his great-grandfather was also a gatekeeper....
No one knows if the gatekeeping job is somehow formalized, but it just kept being passed down.
By the time it reached his generation, that supreme being suddenly disappeared, and he was born into unemployment!
The ancestral job was gone, so the Dark Demon Ape descended into this world, trying his luck to see if he could advance his cultivation further.
That stone staff in his hand is actually a staff used to brace doors.
After the supreme being disappeared, the dojo was divided by disciples, and his father, old and weak at the time, couldn't compete with the other disciples and only got that door-bracing staff.
