After you shut down Stonehenge Base, you find out that Apple Kid returned the shyness book to the Onett Library.
Get the Library Book
In Onett, go to the library. In the first room of the library, go to the left side and talk to the guy wearing a mask. He says to check the bookshelves to find the book.
Go into the door on the right, and check the bookshelf on the left to find the book.
Help the Tenda
After you get the book, you can visit your house if you want, then Teleport to the Tenda Village. Use the Shyness book on the village chief (the one with horns) and he will read it to everybody. Then he will give you some Tendakraut, and the Photo Man will take everybody's picture. And then you will be asked to confirm the player's name that you first entered in Toto when Tony called you. Be sure to talk to the village chief again to get a Bag of Dragonite.
After that, talk to the Tenda on the left to have some tea.
Now you can use the item shop in the northwest of the Tenda Village. However, this item shop only accepts Horns of Life as payment. You can buy Horns of Life in Saturn Valley. Each time you give a Horn of Life to the Tenda who runs the item shop, he gives you the next item on his list. Buy seven Horns of Life in Saturn Valley if you want everything that the Tenda item shop carries.
Before you continue on, make sure that you have the Franklin Badge. Also, you should get Jeff's Neutralizer or Shield-killer from Escargo Express if you don't have it with you. It's also a good idea to buy some Multi bottle rockets if you don't have any. Teleport to the Deep Darkness and buy some from the arms dealer nearby if you need some.
Lumine Hall Cave
When you are ready, talk to the Tenda in the southwest part of the village and he will lift the rock for you. Go down the rope, then talk to the talking rock if you wish, then go through the door to the next room.
Go north, then the path will split. Go south at the split, and go down the ladder there. Go northwest from the ladder to find a talking rock, and a gift box that contains a Super Bomb. Go southwest and go back up the ladder.
Go north, then go west. Ignore the hole that you walk past, then go down the ladder at the end. From there, go south. Go past the ladder to find a gift box that contains an IQ Capsule. Then go up the nearest ladder.
Go east to find a gift box that contains a Diadem of Kings for Poo. Then go west and go down the ladder again. Go north from there and go up the northern ladder.
Go east, then go north when you can. The path will go northeast, then south. At that point, go as far south as you can go, and you will find a gift box that contains a Luck Capsule. Go down the ladder to the left of that gift box.
Talk to the talking rock if you wish. Then follow the path, and when it splits, go to the left to find a gift box that contains Rock Candy. Then go north and follow the path from there. Don't go up the ladder on the left yet. First, go to the east and open the gift box to get a Bottle of DXWater. Then go west again and go up the ladder there.
Go northwest and open the gift box to get a Cup of Lifenoodles. Then fall down the hole. Talk to the talking rock if you wish. Then go northeast. Open the gift box on the right to get a Luxury Jerky. Then go northeast and go up the ladder.
Go southwest, but don't talk to the sparkle yet. First, keep going southwest to find a gift box. Open it to get a Rabbit's Foot. Then go northeast and talk to the sparkle to start the boss battle.
You can use a couple of Multi bottle rockets to get rid of Electro Specter quickly. Electro Specter starts the battle with a PSI Shield β, but this doesn't block or deflect physical attacks, so it's safe to start with bottle rockets. Just don't use PSI attacks on it until its shield is gone. Jeff can use the Neutralizer (which has a 100% chance of success) or Shield-killer (which can fail depending on Jeff's luck), or you can just wait for Electro Specter to use its own Neutralizer, which will get rid of its shield.
After Electro Specter is gone, go past where it was standing, and go west to find a hole. Make sure you have the Tendakraut with you. If not, go get it. I also recommend having three Multi bottle rockets with you. You can go buy some if you don't have any. Then fall into the hole that the Electro Specter was guarding.
Go west until a cut scene occurs. After that, go west and fall into the hole.