The BFG explains that he had to take Sophie from her bed because once she saw him, he knew that she would go around telling everyone. The BFG says that he fears what humans would do if they knew that giants existed. They might even put him in a zoo. The BFG also shows Sophie the other giants and explains that he is actually the runt of the lot, with the other giants reaching twice his height.
Sophie details her life at the orphanage under the cruel tutelage of Mrs. Clonkers and the BFG reveals that he can never let her go back to the orphanage, since she knows giants exist. The BFG also explains what he uses his trumpet for - to blow good dreams into the minds of children as they sleep. He collects these dreams by using his enhanced hearing, courtesy of his very large ears.
In fact, it was thanks to his large ears that he could hear Sophie watching him through her window last night. BFG says that his hearing is so sharp he can even here the screams and moans of plants and trees when they are cut or even just twisted.
The BFG also shows Sophie his snozzcumbers - the horrible vegetable that makes up his diet, since he does not eat humans. Sophie tries it and agrees that it tastes bad. She asks why the BFG doesn't simply take better tasting vegetables from the human world, but the BFG protests that that would be stealing.
Suddenly, the giant named the Bloodbottler comes raging into the BFG's cave, accusing him of speaking with and hiding a human being. Sophie hides behind the snozzcumber, and then gets inside it, worried that the giant might see her if he comes too close. However, the BFG tries to distract the Bloodbottler by talking about the snozzcumber, prompting him to take a giant bite out of it - Sophie included!
However, the Bloodbottler is revolted by the taste of the snozzcumber and spits it out without realizing that Sophie was ever inside his mouth. The giant leaves and the BFG is relieved to find Sophie unharmed.
The BFG then introduces Sophie to frobscottle and whizzpoppers, which are the giant equivalent of soda and farts. He explains that farts are considered polite and great fun in the giant world; it's burping that's very rude. Both Sophie and BFG take turns whizzpopping from the frobscottle.
Throughout these next five chapters, the BFG and Sophie build on their budding friendship, sharing secrets and dreams. The BFG reveals that he has always wanted to see an elephant, and Sophie reveals her sad background.
Both Sophie and the BFG don't trust each other just yet. Sophie is still a little afraid of him, and the BFG is afraid of what she will tell other humans. The BFG explains that he has more principles than the other giants.
He describes the other giants as man-eating cannibals. Sophie describes them as ugly with large bellies (34). This is the first time that the BFG and Sophie discuss stopping the giants from eating humans, but the BFG is afraid.
The BFG also explains what countries giants prefer to eat from - Esquimos to cool down, a Hottentot to heat up, etc. (37). He is still afraid that Sophie will tell others about his secrets - the dreams he collects for example. However, he overcomes his misgivings and shares his secrets.
He shows Sophie how he can hear well with his ears and teases her about how deaf she is compared to him. Sophie doesn't believe some of his secrets at first and he is surprised and unhappy about this, until Sophie says she believes him again.