Cultivator ~ The Chronicle of A Retired Knight and Monster Girls' Bustling Pioneering by Flying Panjandrum - Adult Sex Game

Overview:
Forced into exile, the protagonist escapes to a remote sacred mountain.
When he defeated a powerful monster he encountered, to his surprise, it took the form of a girl.
She called herself Meifa, the Arch Demon.
In exchange for being given shelter by Meifa, the protagonist undertakes the quest for the restoration of the mountain.