As Mig and the Pea make their way to the dungeon, with Roscuro hiding in Mig’s pocket, the rest of the castle sleeps. King Phillip dreams that the queen is a bird who keeps calling his name, while Cook dreams that she lost the recipe for the queen’s favorite soup. Despereaux is asleep not far away from Cook, in the pantry, dreaming of knights, darkness, and light. Mig’s candle is the only light in the whole castle.
The Pea, in her glittering party dress, is a beacon of goodness and light in the dark, troubled castle. Cook’s dream speaks to how anxiety-inducing it is for everyone in the castle to no longer be able to make or eat soup: Cook knows the queen would likely have been happy if soup were still legal, but Cook can’t honor the queen’s memory by making soup.
Now, it’s time to talk about the Princess Pea’s heart, since the narrator has described the hearts of all the other characters. The Pea’s heart is complicated, like most hearts are. There are dark parts: she hates Roscuro for killing her mother, and there’s a huge dark spot of sadness for the queen. But Pea is also good, kind and empathetic. To be empathetic means that as the Pea is forced to the dungeon at knifepoint, she can still feel sorry for Mig and how badly Mig must want to be a princess. This is what the princess’s heart looks like as she finally enters the dungeon, just before sunrise.
Just because the Pea is so good, kind, and empathetic doesn’t mean that she doesn’t still have a “complicated” heart that feels dark, difficult emotions. Broadly speaking, this makes the point that a person who is mostly good (or for that matter, mostly bad) is still a complex person with the capacity to be bad (or good). This suggests that Roscuro—a character who is, at this point, mostly evil—may still be able to somehow redeem himself.