Retsu is an elf that survived the massacre because she lived in the forest and teached herself the arts of magic. While she acts friendly and buddy-buddy with Zeraphine, she is actually half-elf and half-spirit due to her parents being like Romeo and Juliet. She is very introverted but isn't shy. She sometimes has trouble to see who are the right persons, and who are trying to use her because she is the only one that is able to perform magic. Retsu doesn't show up until later in the story.