After clearing Plains, you are required to visit the Village just to the right on the world map. The NPC with the golden-colored outfit on the first screen is the Bard, who tells you that all his Music Sheets have been scattered across the land. Should you find any, you can return them to him to get 500 gold for each sheet, as well as the ability to listen to the song attached to that sheet.
On the next screen are the Gastronomer and Magicist, who are able to increase your health and magic, respectively. The Gastronomer requires Meal Tickets, which can be obtained from the NPC directly underneath him, as well as clearing each main area of the bosses. The Magicist just requires gold to increase your magic.
If you go down the ladder, you'll see some more NPCs, one of which will be important in a bit. The one on the far left (Grandma Swamp) will tell you some stats of your game should you talk to her. Hit the door on the left side of the room to find Mona, who will allow you to play a mini-game for a small price of 100 gold.
Go back to the previous room and exit to the right to find some more NPCs. The frog, Croaker, just tells some punny jokes, while Trouppe Acolyte sells two Trouppe Chalices for 1500 gold each. These can be filled up with Ichor from the Trouppe King at Trouppe Pond. The NPC on the far right, Chester, will sell Relics, with two available at the moment.
These Relics are sort of like sub-weapons (of Castlevania fame), which use up magic. If you have the gold, you can purchase them if you want. Note that any time you find Chester (blue chest) during the Knight levels, he will attempt to sell you a Relic. If you don't buy the Relic there, Chester in the Village will have that Relic available, but for an increased price.
You can break the wall on the left side of this room to find Music Sheet #7. Now, head back up to the surface and go right until you see a woman carrying some buckets. Wait until she is as far right as she goes, then hop on her back and then onto the nearby stall. From here, you can hop onto the building and grab Music Sheet #6.
