Foil
Character Role Analysis
Katsa/Po
Katsa is impulsive while Po is deliberate. Katsa is grounded in her physical body, while Po spends most of his time in his mind. Where Katsa is blunt and abrupt ("I struck the first blow, Giddon. Sit down" (9.71)), Po is diplomatic ("Lord Giddon […] If I've insulted your lady […] you must forgive me" (9.76)). And while Katsa tends toward serious, Po is a great laugher, through and through.
Finally, Po is perceptive, while Katsa, so focused on the physical and the information she gets through her five senses, is often the last one to figure out subtleties, like when she misses the fact that Giddon loves her or that she and Po are headed toward romance, which even Raffin knows before she does. The two are like the halves of a Yin-Yang symbol, and seeing them side-by-side helps to sharpen our understanding of them both.