There has been no humor in this book up to this point. It started with people fighting and losing to supernatural beings, an execution, and a man feeling guilt towards taking another person’s life. The chapter I just read is about Daenerys’s brother, Viserys, forcing Dany to presents herself to the Khal Drogo in order to be wed to him. She does not want this, and she told Viserys this. Viserys wants Dany to marry Drogo because he wants to trade her for an army. He states later in the chapter that he would not care who she was with if it meant he could get his army. He even says that he would have her lay with forty thousand men and their horses in exchange for his army. This obviously deeply upsets Dany, but she continues to do whatever Viserys says. I believe this is because he has abused her in the past. It is never outright stated in the chapter, but from what is said and how she acts, I believe this to be true. People who are abused tend not to stand up to those who have abused them, because they are afraid of it happening again.
I do not think that there are many ways humor could have been added to this chapter due to how dark it is, but one way that might have created a lighter tone to this portion of the book is if the khal had been a short, skinny man. He is described as being this incredibly strong and powerful man by one of the ladies who bathes Daenerys. It would have been funny to see him be puny and the complete opposite of what she had described. It also would not have made the scene so harrowing to read, which I believe would have taken a lot away from the scene, and this scene reveals a lot about Dany and Viserys’s characters. Although there could have been some changes to the story to make it more funny and less upsetting, it would not have been a good idea to do so, and the book up to this point has been better without the humor.