Help Guide on front page lists almost all the information available. There isn't a proper walkthrough because you repeat the same events over and over each run. Also because daily events, dungeon appearances, god interactions, and skill checks are random, unless someone save scums new days repeatedly there is no "optimized" walkthrough route. The Help guide does have all character events in order with trigger conditions though.
No commands or cheats. Only grind.
Original scene with priestess and parents was removed for character rework. Parents still have sex for 5 seconds in introduction if you consider that ntr but scene can be opted out by not watching.