After completing the previous quest, we can now accept commissions from residents. Completing these commissions will earn us rewards.
You can view commission quests on the map, but let's stick to the main storyline for now. There's also a treasure chest nearby that we can grab—it's right behind the house.
We're right next to the save point, so let's fast travel directly to the area near the main quest objective.
Enter the room and speak with the objective marker.
A new system notification will appear after the dialogue ends. You can now see the "Oni's Secret Door" marked on the map. There's one along the main quest path we're about to take.
Head to the save point to upgrade your character before triggering the next event.
When you reach the vicinity of the objective, climb up using the stairs outside.
After jumping down, you'll find that the door here is locked.
However, there's a hole in the wooden plank on the left. We can use our bow and arrow to shoot the lock open.
Open the door and enter. The objective is at the bottom of the well, so let's go down.
After coming down, keep moving inward. When you reach the side of the mechanism, shoot it with your bow and arrow.
After destroying it, head back up. Climb upward and cross over via the mechanism we just knocked down.
Watch the following cutscene to complete this quest.

