I don’t understand the jump from chapter 3 to 4

From what I understood, they did intimate stuffs on chapter 3 right? Even if it's not penetration, I think that caused the ml to remember stuffs and was able to speak. They just didn't show him speaking, so it was up to our imagination. You can see on the last panel of chapter 3 that the ml understood what the mc said about the shivering puppy. And so yeah, I think it's easy to understand when you get down to it