In this chapter, we learn that the girl in the next room is teasing the boy while everyone is asleep. The boy tries to push the girl's pant, but the girl pushes him back, saying that he's selfish to push until the end. The girl says that she's never done anything like this before, and the boy says that he can't believe that she can do such a thing. He's a beginner, he says, so he'll have to learn how to use the weapon. He pushes the pant until it creaks, and he can feel his organs. He says that if he pushes it too hard, it'll sink into his belly, and it will feel like he has "crushed his lungs" . But he pushes too hard and the pant creaks again, and this time it feels like it's "beating under my belly" , which is a big deal for him. He thanks the girl for pushing him so hard, and says that this is "really big" for him, because he hasn't felt this way before