For people who don't understand the seating choices/think the character selection seems random:

Dawn/Hikari as Mythra/Hikari cuz they share the same Japanese name.

Serena as Pyra/Homura because her main pokemon is a fire type, is good at cooking, and changed her long hair to short hair after experiencing a certain setback.

and finally Lillie as Nia for being the noble lady, and her having a giant white feline travel companion friend.

God like